upstream/emscripten/src/settings.js

// Settings that control the emscripten compiler.  These are available to the
// python code and also as global variables when the JS compiler runs. They
// are set via the command line.  For example:
//
//   emcc -sOPTION1=VALUE1 -sOPTION2=ITEM1,ITEM2 [..other stuff..]
//
// For convenience and readability ``-sOPTION`` expands to ``-sOPTION=1``
// and ``-sNO_OPTION`` expands to ``-sOPTION=0`` (assuming OPTION is a valid
// option).
//
// See https://github.com/emscripten-core/emscripten/wiki/Code-Generation-Modes/
//
// Note that the values here are the defaults which can be affected either
// directly via ``-s`` flags or indirectly via other options (e.g. -O1,2,3)
//
// These flags should only have an effect when compiling to JS, so there
// should not be a need to have them when just compiling source to
// bitcode. However, there will also be no harm either, so it is ok to.
//
// Settings in this file can be directly set from the command line.  Internal
// settings that are not part of the user ABI live in the settings_internal.js.
//
// In general it is best to pass the same arguments at both compile and link
// time, as whether wasm object files are used or not affects when codegen
// happens (without wasm object files, codegen is done entirely during
// link; otherwise, it is during compile). Flags affecting codegen must
// be passed when codegen happens, so to let a build easily switch when codegen
// happens (LTO vs normal), pass the flags at both times. The flags are also
// annotated in this file:
//
// [link] - Should be passed at link time. This is the case for all JS flags,
//          as we emit JS at link (and that is most of the flags here, and
//          hence the default).
// [compile+link] - A flag that has an effect at both compile and link time,
//                  basically any time emcc is invoked. The same flag should be
//                  passed at both times in most cases.
//
// If not otherwise specified, a flag is [link]. Note that no flag is only
// relevant during compile time, as during link we may do codegen for system
// libraries and other support code, so all flags are either link or
// compile+link.
//

// Tuning

// Whether we should add runtime assertions. This affects both JS and how
// system libraries are built.
// ASSERTIONS == 2 gives even more runtime checks, that may be very slow. That
// includes internal dlmalloc assertions, for example.
// ASSERTIONS defaults to 0 in optimized builds (-O1 and above).
// [link]
var ASSERTIONS = 1;

// Chooses what kind of stack smash checks to emit to generated code:
// Building with ASSERTIONS=1 causes STACK_OVERFLOW_CHECK default to 1.
// Since ASSERTIONS=1 is the default at -O0, which itself is the default
// optimization level this means that this setting also effectively
// defaults to 1, absent any other settings:
//
// - 0: Stack overflows are not checked.
// - 1: Adds a security cookie at the top of the stack, which is checked at end
//   of each tick and at exit (practically zero performance overhead)
// - 2: Same as above, but also runs a binaryen pass which adds a check to all
//   stack pointer assignments. Has a small performance cost.
//
// [link]
var STACK_OVERFLOW_CHECK = 0;

// When :ref`STACK_OVERFLOW_CHECK` is enabled we also check writes to address
// zero. This can help detect NULL pointer usage.  If you want to skip this
// extra check (for example, if you want reads from the address zero to always
// return zero) you can disable this here.  This setting has no effect when
// :ref:`STACK_OVERFLOW_CHECK` is disabled.
var CHECK_NULL_WRITES = true;

// When set to 1, will generate more verbose output during compilation.
// [general]
var VERBOSE = false;

// Whether we will run the main() function. Disable if you embed the generated
// code in your own, and will call main() yourself at the right time (which you
// can do with Module.callMain(), with an optional parameter of commandline args).
// [link]
var INVOKE_RUN = true;

// If 0, support for shutting down the runtime is not emitted into the build.
// This means that the program is not quit when main() completes, but execution
// will yield to the event loop of the JS environment, allowing event handlers
// to run afterwards. If 0, C++ global destructors will not be emitted into the
// build either, to save on code size. Calling exit() will throw an unwinding
// exception, but will not shut down the runtime.
//
// Set this to 1 if you do want to retain the ability to shut down the program.
// If 1, then completing main() will by default call exit(), unless a refcount
// keeps the runtime alive. Call emscripten_exit_with_live_runtime() to finish
// main() while keeping the runtime alive. Calling emscripten_force_exit() will
// shut down the runtime, invoking atexit()s, and flushing stdio streams.
// This setting is controlled automatically in :ref:`STANDALONE_WASM` mode:
//
// - For a command (has a main function) this is always 1
// - For a reactor (no main function) this is always 0
//
// For more details, see documentation for emscripten_force_exit() and
// emscripten_exit_with_live_runtime().
// [link]
var EXIT_RUNTIME = false;

// The total stack size. There is no way to enlarge the stack, so this
// value must be large enough for the program's requirements. If
// assertions are on, we will assert on not exceeding this, otherwise,
// it will fail silently.
// [link]
var STACK_SIZE = 64*1024;

// What malloc()/free() to use, out of:
//
//   - dlmalloc - a powerful general-purpose malloc
//   - emmalloc - a simple and compact malloc designed for emscripten
//   - emmalloc-debug - use emmalloc and add extra assertion checks
//   - emmalloc-memvalidate - use emmalloc with assertions+heap consistency
//     checking.
//   - emmalloc-verbose - use emmalloc with assertions + verbose logging.
//   - emmalloc-memvalidate-verbose - use emmalloc with assertions + heap
//     consistency checking + verbose logging.
//   - mimalloc - a powerful multithreaded allocator. This is recommended in
//     large applications that have malloc() contention, but it is
//     larger and uses more memory.
//   - none - no malloc() implementation is provided, but you must implement
//     malloc() and free() yourself.
//
// dlmalloc is necessary for split memory and other special modes, and will be
// used automatically in those cases.
// In general, if you don't need one of those special modes, and if you don't
// allocate very many small objects, you should use emmalloc since it's
// smaller. Otherwise, if you do allocate many small objects, dlmalloc
// is usually worth the extra size. dlmalloc is also a good choice if you want
// the extra security checks it does (such as noticing metadata corruption in
// its internal data structures, which emmalloc does not do).
// [link]
var MALLOC = "dlmalloc";

// If 1, then when malloc would fail we abort(). This is nonstandard behavior,
// but makes sense for the web since we have a fixed amount of memory that
// must all be allocated up front, and so (a) failing mallocs are much more
// likely than on other platforms, and (b) people need a way to find out
// how big that initial allocation (INITIAL_MEMORY) must be.
// If you set this to 0, then you get the standard malloc behavior of
// returning NULL (0) when it fails.
//
// Setting ALLOW_MEMORY_GROWTH turns this off, as in that mode we default to
// the behavior of trying to grow and returning 0 from malloc on failure, like
// a standard system would. However, you can still set this flag to override
// that.  This is a mostly-backwards-compatible change. Previously this option
// was ignored when growth was on. The current behavior is that growth turns it
// off by default, so for users that never specified the flag nothing changes.
// But if you do specify it, it will have an effect now, which it did not
// previously. If you don't want that, just stop passing it in at link time.
//
// Note that this setting does not affect the behavior of operator new in C++.
// This function will always abort on allocation failure if exceptions are
// disabled.
// If you want new to return 0 on failure, use it with std::nothrow.
//
// [link]
var ABORTING_MALLOC = true;

// The initial amount of heap memory available to the program.  This is the
// memory region available for dynamic allocations via `sbrk`, `malloc` and `new`.
//
// Unlike INITIAL_MEMORY, this setting allows the static and dynamic regions of
// your program's memory to independently grow. In most cases we recommend using
// this setting rather than `INITIAL_MEMORY`. However, this setting does not work
// for imported memories (e.g. when dynamic linking is used).
//
// [link]
var INITIAL_HEAP = 16777216;

// The initial amount of memory to use. Using more memory than this will
// cause us to expand the heap, which can be costly with typed arrays:
// we need to copy the old heap into a new one in that case.
// If ALLOW_MEMORY_GROWTH is set, this initial amount of memory can increase
// later; if not, then it is the final and total amount of memory.
//
// By default, this value is calculated based on INITIAL_HEAP, STACK_SIZE,
// as well the size of static data in input modules.
//
// (This option was formerly called TOTAL_MEMORY.)
// [link]
var INITIAL_MEMORY = -1;

// Set the maximum size of memory in the wasm module (in bytes). This is only
// relevant when ALLOW_MEMORY_GROWTH is set, as without growth, the size of
// INITIAL_MEMORY is the final size of memory anyhow.
//
// Note that the default value here is 2GB, which means that by default if you
// enable memory growth then we can grow up to 2GB but no higher. 2GB is a
// natural limit for several reasons:
//
//   * If the maximum heap size is over 2GB, then pointers must be unsigned in
//     JavaScript, which increases code size. We don't want memory growth builds
//     to be larger unless someone explicitly opts in to >2GB+ heaps.
//   * Historically no VM has supported more >2GB+, and only recently (Mar 2020)
//     has support started to appear. As support is limited, it's safer for
//     people to opt into >2GB+ heaps rather than get a build that may not
//     work on all VMs.
//
// To use more than 2GB, set this to something higher, like 4GB.
//
// (This option was formerly called WASM_MEM_MAX and BINARYEN_MEM_MAX.)
// [link]
var MAXIMUM_MEMORY = 2147483648;

// If false, we abort with an error if we try to allocate more memory than
// we can (INITIAL_MEMORY). If true, we will grow the memory arrays at
// runtime, seamlessly and dynamically.
// See https://code.google.com/p/v8/issues/detail?id=3907 regarding
// memory growth performance in chrome.
// Note that growing memory means we replace the JS typed array views, as
// once created they cannot be resized. (In wasm we can grow the Memory, but
// still need to create new views for JS.)
// Setting this option on will disable ABORTING_MALLOC, in other words,
// ALLOW_MEMORY_GROWTH enables fully standard behavior, of both malloc
// returning 0 when it fails, and also of being able to allocate more
// memory from the system as necessary.
// [link]
var ALLOW_MEMORY_GROWTH = false;

// If ALLOW_MEMORY_GROWTH is true, this variable specifies the geometric
// overgrowth rate of the heap at resize. Specify MEMORY_GROWTH_GEOMETRIC_STEP=0
// to disable overgrowing the heap at all, or e.g.
// MEMORY_GROWTH_GEOMETRIC_STEP=1.0 to double the heap (+100%) at every grow step.
// The larger this value is, the more memory the WebAssembly heap overreserves
// to reduce performance hiccups coming from memory resize, and the smaller
// this value is, the more memory is conserved, at the performance of more
// stuttering when the heap grows. (profiled to be on the order of ~20 msecs)
// [link]
var MEMORY_GROWTH_GEOMETRIC_STEP = 0.20;

// Specifies a cap for the maximum geometric overgrowth size, in bytes. Use
// this value to constrain the geometric grow to not exceed a specific rate.
// Pass MEMORY_GROWTH_GEOMETRIC_CAP=0 to disable the cap and allow unbounded
// size increases.
// [link]
var MEMORY_GROWTH_GEOMETRIC_CAP = 96*1024*1024;

// If ALLOW_MEMORY_GROWTH is true and MEMORY_GROWTH_LINEAR_STEP == -1, then
// geometric memory overgrowth is utilized (above variable). Set
// MEMORY_GROWTH_LINEAR_STEP to a multiple of WASM page size (64KB), eg. 16MB to
// replace geometric overgrowth rate with a constant growth step size. When
// MEMORY_GROWTH_LINEAR_STEP is used, the variables MEMORY_GROWTH_GEOMETRIC_STEP
// and MEMORY_GROWTH_GEOMETRIC_CAP are ignored.
// [link]
var MEMORY_GROWTH_LINEAR_STEP = -1;

// The "architecture" to compile for. 0 means the default wasm32, 1 is
// the full end-to-end wasm64 mode, and 2 is wasm64 for clang/lld but lowered to
// wasm32 in Binaryen (such that it can run on wasm32 engines, while internally
// using i64 pointers).
// Assumes WASM_BIGINT.
// [compile+link]
var MEMORY64 = 0;

// Sets the initial size of the table when MAIN_MODULE or SIDE_MODULE is used
// (and not otherwise). Normally Emscripten can determine the size of the table
// at link time, but in SPLIT_MODULE mode, wasm-split often needs to grow the
// table, so the table size baked into the JS for the instrumented build will be
// too small after the module is split. This is a hack to allow users to specify
// a large enough table size that can be consistent across both builds. This
// setting may be removed at any time and should not be used except in
// conjunction with SPLIT_MODULE and dynamic linking.
// [link]
var INITIAL_TABLE = -1;

// If true, allows more functions to be added to the table at runtime. This is
// necessary for dynamic linking, and set automatically in that mode.
// [link]
var ALLOW_TABLE_GROWTH = false;

// Where global data begins; the start of static memory.
// A GLOBAL_BASE of 1024 or above is useful for optimizing load/store offsets,
// as it enables the --low-memory-unused pass
// [link]
var GLOBAL_BASE = 1024;

// Where table slots (function addresses) are allocated.
// This must be at least 1 to reserve the zero slot for the null pointer.
// [link]
var TABLE_BASE = 1;

// Whether closure compiling is being run on this output
// [link]
var USE_CLOSURE_COMPILER = false;

// Deprecated: Use the standard warnings flags instead. e.g. ``-Wclosure``,
// ``-Wno-closure``, ``-Werror=closure``.
// options: 'quiet', 'warn', 'error'. If set to 'warn', Closure warnings are
// printed out to console. If set to 'error', Closure warnings are treated like
// errors, similar to -Werror compiler flag.
// [link]
// [deprecated]
var CLOSURE_WARNINGS = 'quiet';

// Ignore closure warnings and errors (like on duplicate definitions)
// [link]
var IGNORE_CLOSURE_COMPILER_ERRORS = false;

// If set to 1, each wasm module export is individually declared with a
// JavaScript "var" definition. This is the simple and recommended approach.
// However, this does increase code size (especially if you have many such
// exports), which can be avoided in an unsafe way by setting this to 0. In that
// case, no "var" is created for each export, and instead a loop (of small
// constant code size, no matter how many exports you have) writes all the
// exports received into the global scope. Doing so is dangerous since such
// modifications of the global scope can confuse external JS minifier tools, and
// also things can break if the scope the code is in is not the global scope
// (e.g. if you manually enclose them in a function scope).
// [link]
var DECLARE_ASM_MODULE_EXPORTS = true;

// If set to 1, prevents inlining. If 0, we will inline normally in LLVM.
// This does not affect the inlining policy in Binaryen.
// [compile]
var INLINING_LIMIT = false;

// If set to 1, perform an acorn pass that converts each HEAP access into a
// function call that uses DataView to enforce LE byte order for HEAP buffer;
// This makes generated JavaScript run on BE as well as LE machines. (If 0, only
// LE systems are supported). Does not affect generated wasm.
// [experimental]
var SUPPORT_BIG_ENDIAN = false;

// Check each write to the heap, for example, this will give a clear
// error on what would be segfaults in a native build (like dereferencing
// 0). See runtime_safe_heap.js for the actual checks performed.
// Set to value 1 to test for safe behavior for both Wasm+Wasm2JS builds.
// Set to value 2 to test for safe behavior for only Wasm builds. (notably,
// Wasm-only builds allow unaligned memory accesses. Note, however, that
// on some architectures unaligned accesses can be very slow, so it is still
// a good idea to verify your code with the more strict mode 1)
// [link]
var SAFE_HEAP = 0;

// Log out all SAFE_HEAP operations
// [link]
var SAFE_HEAP_LOG = false;

// Allows function pointers to be cast, wraps each call of an incorrect type
// with a runtime correction.  This adds overhead and should not be used
// normally.  Aside from making calls not fail, this tries to convert values as
// best it can.  We use 64 bits (i64) to represent values, as if we wrote the
// sent value to memory and loaded the received type from the same memory (using
// truncs/extends/ reinterprets). This means that when types do not match the
// emulated values may not match (this is true of native too, for that matter -
// this is all undefined behavior). This approach appears good enough to
// support Python (the original motivation for this feature) and Glib (the
// continued motivation).
// [link]
var EMULATE_FUNCTION_POINTER_CASTS = false;

// Print out exceptions in emscriptened code.
// [link]
var EXCEPTION_DEBUG = false;

// Print out when we enter a library call (library*.js). You can also unset
// runtimeDebug at runtime for logging to cease, and can set it when you want
// it back. A simple way to set it in C++ is::
//
//   emscripten_run_script("runtimeDebug = ...;");
//
// [link]
var LIBRARY_DEBUG = false;

// Print out all musl syscalls, including translating their numeric index
// to the string name, which can be convenient for debugging. (Other system
// calls are not numbered and already have clear names; use :ref:`LIBRARY_DEBUG`
// to get logging for all of them.)
// [link]
var SYSCALL_DEBUG = false;

// Log out socket/network data transfer.
// [link]
var SOCKET_DEBUG = false;

// Log dynamic linker information
// [link]
var DYLINK_DEBUG = 0;

// Register file system callbacks using trackingDelegate in library_fs.js
// [link]
var FS_DEBUG = false;

// Select socket backend, either webrtc or websockets. XXX webrtc is not
// currently tested, may be broken

// As well as being configurable at compile time via the "-s" option the
// WEBSOCKET_URL and WEBSOCKET_SUBPROTOCOL
// settings may be configured at run time via the Module object e.g.
// Module['websocket'] = {subprotocol: 'base64, binary, text'};
// Module['websocket'] = {url: 'wss://', subprotocol: 'base64'};
// You can set 'subprotocol' to null, if you don't want to specify it.
// Run time configuration may be useful as it lets an application select
// multiple different services.
// [link]
var SOCKET_WEBRTC = false;

// A string containing either a WebSocket URL prefix (ws:// or wss://) or a
// complete RFC 6455 URL - "ws[s]:" "//" host [ ":" port ] path [ "?" query ].
// In the (default) case of only a prefix being specified the URL will be
// constructed from prefix + addr + ':' + port
// where addr and port are derived from the socket connect/bind/accept calls.
// [link]
var WEBSOCKET_URL = 'ws://';

// If 1, the POSIX sockets API uses a native bridge process server to proxy
// sockets calls from browser to native world.
// [link]
var PROXY_POSIX_SOCKETS = false;

// A string containing a comma separated list of WebSocket subprotocols
// as would be present in the Sec-WebSocket-Protocol header.
// You can set 'null', if you don't want to specify it.
// [link]
var WEBSOCKET_SUBPROTOCOL = 'binary';

// Print out debugging information from our OpenAL implementation.
// [link]
var OPENAL_DEBUG = false;

// If 1, prints out debugging related to calls from ``emscripten_web_socket_*``
// functions in ``emscripten/websocket.h``.
// If 2, additionally traces bytes communicated via the sockets.
// [link]
var WEBSOCKET_DEBUG = false;

// Adds extra checks for error situations in the GL library. Can impact
// performance.
// [link]
var GL_ASSERTIONS = false;

// If enabled, prints out all API calls to WebGL contexts. (*very* verbose)
// [link]
var TRACE_WEBGL_CALLS = false;

// Enables more verbose debug printing of WebGL related operations. As with
// LIBRARY_DEBUG, this is toggleable at runtime with option GL.debug.
// [link]
var GL_DEBUG = false;

// When enabled, sets preserveDrawingBuffer in the context, to allow tests to
// work (but adds overhead)
// [link]
var GL_TESTING = false;

// How large GL emulation temp buffers are
// [link]
var GL_MAX_TEMP_BUFFER_SIZE = 2097152;

// Enables some potentially-unsafe optimizations in GL emulation code
// [link]
var GL_UNSAFE_OPTS = true;

// Forces support for all GLES2 features, not just the WebGL-friendly subset.
// [link]
var FULL_ES2 = false;

// If true, glGetString() for GL_VERSION and GL_SHADING_LANGUAGE_VERSION will
// return strings OpenGL ES format "Open GL ES ... (WebGL ...)" rather than the
// WebGL format. If false, the direct WebGL format strings are returned. Set
// this to true to make GL contexts appear like an OpenGL ES context in these
// version strings (at the expense of a little bit of added code size), and to
// false to make GL contexts appear like WebGL contexts and to save some bytes
// from the output.
// [link]
var GL_EMULATE_GLES_VERSION_STRING_FORMAT = true;

// If true, all GL extensions are advertised in unprefixed WebGL extension
// format, but also in desktop/mobile GLES/GL extension format with ``GL_``
// prefix.
// [link]
var GL_EXTENSIONS_IN_PREFIXED_FORMAT = true;

// If true, adds support for automatically enabling all GL extensions for
// GLES/GL emulation purposes. This takes up code size. If you set this to 0,
// you will need to manually enable the extensions you need.
// [link]
var GL_SUPPORT_AUTOMATIC_ENABLE_EXTENSIONS = true;

// If true, the function ``emscripten_webgl_enable_extension()`` can be called
// to enable any WebGL extension. If false, to save code size,
// ``emscripten_webgl_enable_extension()`` cannot be called to enable any of
// extensions 'ANGLE_instanced_arrays', 'OES_vertex_array_object',
// 'WEBGL_draw_buffers', 'WEBGL_multi_draw',
// 'WEBGL_draw_instanced_base_vertex_base_instance', or
// 'WEBGL_multi_draw_instanced_base_vertex_base_instance',
// but the dedicated functions ``emscripten_webgl_enable_*()``
// found in html5.h are used to enable each of those extensions.
// This way code size is increased only for the extensions that are actually used.
// N.B. if setting this to 0, GL_SUPPORT_AUTOMATIC_ENABLE_EXTENSIONS must be set
// to zero as well.
// [link]
var GL_SUPPORT_SIMPLE_ENABLE_EXTENSIONS = true;

// If set to 0, Emscripten GLES2->WebGL translation layer does not track the
// kind of GL errors that exist in GLES2 but do not exist in WebGL. Setting
// this to 0 saves code size. (Good to keep at 1 for development)
// [link]
var GL_TRACK_ERRORS = true;

// If true, GL contexts support the explicitSwapControl context creation flag.
// Set to 0 to save a little bit of space on projects that do not need it.
// [link]
var GL_SUPPORT_EXPLICIT_SWAP_CONTROL = false;

// If true, calls to glUniform*fv and glUniformMatrix*fv utilize a pool of
// preallocated temporary buffers for common small sizes to avoid generating
// temporary garbage for WebGL 1. Disable this to optimize generated size of the
// GL library a little bit, at the expense of generating garbage in WebGL 1. If
// you are only using WebGL 2 and do not support WebGL 1, this is not needed and
// you can turn it off.
// [link]
var GL_POOL_TEMP_BUFFERS = true;

// If true, enables support for the EMSCRIPTEN_explicit_uniform_location WebGL
// extension. See docs/EMSCRIPTEN_explicit_uniform_location.txt
var GL_EXPLICIT_UNIFORM_LOCATION = false;

// If true, enables support for the EMSCRIPTEN_uniform_layout_binding WebGL
// extension. See docs/EMSCRIPTEN_explicit_uniform_binding.txt
var GL_EXPLICIT_UNIFORM_BINDING = false;

// Deprecated. Pass -sMAX_WEBGL_VERSION=2 to target WebGL 2.0.
// [link]
var USE_WEBGL2 = false;

// Specifies the lowest WebGL version to target. Pass -sMIN_WEBGL_VERSION=1
// to enable targeting WebGL 1, and -sMIN_WEBGL_VERSION=2 to drop support
// for WebGL 1.0
// [link]
var MIN_WEBGL_VERSION = 1;

// Specifies the highest WebGL version to target. Pass -sMAX_WEBGL_VERSION=2
// to enable targeting WebGL 2. If WebGL 2 is enabled, some APIs (EGL, GLUT, SDL)
// will default to creating a WebGL 2 context if no version is specified.
// Note that there is no automatic fallback to WebGL1 if WebGL2 is not supported
// by the user's device, even if you build with both WebGL1 and WebGL2
// support, as that may not always be what the application wants. If you want
// such a fallback, you can try to create a context with WebGL2, and if that
// fails try to create one with WebGL1.
// [link]
var MAX_WEBGL_VERSION = 1;

// If true, emulates some WebGL 1 features on WebGL 2 contexts, meaning that
// applications that use WebGL 1/GLES 2 can initialize a WebGL 2/GLES3 context,
// but still keep using WebGL1/GLES 2 functionality that no longer is supported
// in WebGL2/GLES3. Currently this emulates GL_EXT_shader_texture_lod extension
// in GLSL ES 1.00 shaders, support for unsized internal texture formats, and the
// GL_HALF_FLOAT_OES != GL_HALF_FLOAT mixup.
// [link]
var WEBGL2_BACKWARDS_COMPATIBILITY_EMULATION = false;

// Forces support for all GLES3 features, not just the WebGL2-friendly subset.
// This automatically turns on FULL_ES2 and WebGL2 support.
// [link]
var FULL_ES3 = false;

// Includes code to emulate various desktop GL features. Incomplete but useful
// in some cases, see
// http://kripken.github.io/emscripten-site/docs/porting/multimedia_and_graphics/OpenGL-support.html
// [link]
var LEGACY_GL_EMULATION = false;

// If you specified LEGACY_GL_EMULATION = 1 and only use fixed function pipeline
// in your code, you can also set this to 1 to signal the GL emulation layer
// that it can perform extra optimizations by knowing that the user code does
// not use shaders at all. If LEGACY_GL_EMULATION = 0, this setting has no
// effect.
// [link]
var GL_FFP_ONLY = false;

// If you want to create the WebGL context up front in JS code, set this to 1
// and set Module['preinitializedWebGLContext'] to a precreated WebGL context.
// WebGL initialization afterwards will use this GL context to render.
// [link]
var GL_PREINITIALIZED_CONTEXT = false;

// Enables building of stb-image, a tiny public-domain library for decoding
// images, allowing decoding of images without using the browser's built-in
// decoders. The benefit is that this can be done synchronously, however, it
// will not be as fast as the browser itself.  When enabled, stb-image will be
// used automatically from IMG_Load and IMG_Load_RW. You can also call the
// ``stbi_*`` functions directly yourself.
// [link]
var STB_IMAGE = false;

// From Safari 8 (where WebGL was introduced to Safari) onwards, OES_texture_half_float and OES_texture_half_float_linear extensions
// are broken and do not function correctly, when used as source textures.
// See https://webkit.org/b/183321, https://webkit.org/b/169999,
// https://stackoverflow.com/questions/54248633/cannot-create-half-float-oes-texture-from-uint16array-on-ipad
// [link]
var GL_DISABLE_HALF_FLOAT_EXTENSION_IF_BROKEN = false;

// Workaround Safari WebGL issue: After successfully acquiring WebGL context on a canvas,
// calling .getContext() will always return that context independent of which 'webgl' or 'webgl2'
// context version was passed. See https://webkit.org/b/222758 and
// https://github.com/emscripten-core/emscripten/issues/13295.
// Set this to 0 to force-disable the workaround if you know the issue will not affect you.
// [link]
var GL_WORKAROUND_SAFARI_GETCONTEXT_BUG = true;

// If 1, link with support to glGetProcAddress() functionality.
// In WebGL, glGetProcAddress() causes a substantial code size and performance impact, since WebGL
// does not natively provide such functionality, and it must be emulated. Using glGetProcAddress()
// is not recommended. If you still need to use this, e.g. when porting an existing renderer,
// you can link with -sGL_ENABLE_GET_PROC_ADDRESS to get support for this functionality.
// [link]
var GL_ENABLE_GET_PROC_ADDRESS = true;

// Use JavaScript math functions like Math.tan. This saves code size as we can avoid shipping
// compiled musl code. However, it can be significantly slower as it calls out to JS. It
// also may give different results as JS math is specced somewhat differently than libc, and
// can also vary between browsers.
// [link]
var JS_MATH = false;

// Set this to enable compatibility emulations for old JavaScript engines. This gives you
// the highest possible probability of the code working everywhere, even in rare old
// browsers and shell environments. Specifically:
//
// - Disable WebAssembly. (Must be paired with -sWASM=0)
// - Adjusts MIN_X_VERSION settings to 0 to include support for all browser versions.
// - Avoid TypedArray.fill, if necessary, in zeroMemory utility function.
//
// You can also configure the above options individually.
// [link]
var LEGACY_VM_SUPPORT = false;

// Specify which runtime environments the JS output will be capable of running
// in.  For maximum portability this can be configured to support all
// environments or it can be limited to reduce overall code size.  The supported
// environments are:
//
// - 'web'     - the normal web environment.
// - 'webview' - just like web, but in a webview like Cordova; considered to be
//   same as "web" in almost every place
// - 'worker'  - a web worker environment.
// - 'worklet' - Audio Worklet environment.
// - 'node'    - Node.js.
// - 'shell'   - a JS shell like d8, js, or jsc.
//
// This setting can be a comma-separated list of these environments, e.g.,
// "web,worker". If this is the empty string, then all environments are
// supported.
//
// Certain settings will automatically add to this list.  For examble, building
// with pthreads will automatically add `worker` and building with
// ``AUDIO_WORKLET`` will automatically add `worklet`.
//
// Note that the set of environments recognized here is not identical to the
// ones we identify at runtime using ``ENVIRONMENT_IS_*``. Specifically:
//
// - We detect whether we are a pthread at runtime, but that's set for workers
//   and not for the main file so it wouldn't make sense to specify here.
// - The webview target is basically a subset of web. It must be specified
//   alongside web (e.g. "web,webview") and we only use it for code generation
//   at compile time, there is no runtime behavior change.
//
// Note that by default we do not include the 'shell' environment since direct
// usage of d8, spidermonkey and jsc is extremely rare.
// [link]
var ENVIRONMENT = ['web', 'webview', 'worker', 'node'];

// Enable this to support lz4-compressed file packages. They are stored compressed in memory, and
// decompressed on the fly, avoiding storing the entire decompressed data in memory at once.
// If you run the file packager separately, you still need to build the main program with this flag,
// and also pass --lz4 to the file packager.
// (You can also manually compress one on the client, using LZ4.loadPackage(), but that is less
// recommended.)
// Limitations:
//
// - LZ4-compressed files are only decompressed when needed, so they are not available
//   for special preloading operations like pre-decoding of images using browser codecs,
//   preloadPlugin stuff, etc.
// - LZ4 files are read-only.
//
// [link]
var LZ4 = false;

// Emscripten (JavaScript-based) exception handling options.
// The three related settings (:ref:`DISABLE_EXCEPTION_CATCHING`,
// :ref:`EXCEPTION_CATCHING_ALLOWED`, and :ref:`DISABLE_EXCEPTION_THROWING`)
// only pertain to JavaScript-based exception handling and do not control the
// native Wasm exception handling option (``-fwasm-exceptions``)

// Disables generating code to actually catch exceptions. This disabling is on
// by default as the overhead of exceptions is quite high in size and speed
// currently (in the future, wasm should improve that). When exceptions are
// disabled, if an exception actually happens then it will not be caught
// and the program will halt (so this will not introduce silent failures).
//
// .. note::
//
//   This removes *catching* of exceptions, which is the main
//   issue for speed, but you should build source files with
//   -fno-exceptions to really get rid of all exceptions code overhead,
//   as it may contain thrown exceptions that are never caught (e.g.
//   just using std::vector can have that). -fno-rtti may help as well.
//
// This option is mutually exclusive with :ref:`EXCEPTION_CATCHING_ALLOWED`.
//
// This option only applies to Emscripten (JavaScript-based) exception handling
// and does not control the native Wasm exception handling.
//
// [compile+link]
var DISABLE_EXCEPTION_CATCHING = 1;

// Enables catching exception but only in the listed functions.  This
// option acts like a more precise version of ``DISABLE_EXCEPTION_CATCHING=0``.
//
// This option is mutually exclusive with :ref:`DISABLE_EXCEPTION_CATCHING`.
//
// This option only applies to Emscripten (JavaScript-based) exception handling
// and does not control the native Wasm exception handling.
//
// [compile+link]
var EXCEPTION_CATCHING_ALLOWED = [];

// Internal: Tracks whether Emscripten should link in exception throwing (C++
// 'throw') support library. This does not need to be set directly, but pass
// -fno-exceptions to the build disable exceptions support. (This is basically
// -fno-exceptions, but checked at final link time instead of individual .cpp
// file compile time) If the program *does* contain throwing code (some source
// files were not compiled with ``-fno-exceptions``), and this flag is set at link
// time, then you will get errors on undefined symbols, as the exception
// throwing code is not linked in. If so you should either unset the option (if
// you do want exceptions) or fix the compilation of the source files so that
// indeed no exceptions are used).
//
// This option only applies to Emscripten (JavaScript-based) exception handling
// and does not control the native Wasm exception handling.
//
// [compile+link]
var DISABLE_EXCEPTION_THROWING = false;

// Make the exception message printing function, 'getExceptionMessage' available
// in the JS library for use, by adding necessary symbols to
// :ref:`EXPORTED_FUNCTIONS`.
//
// This works with both Emscripten EH and Wasm EH. When you catch an exception
// from JS, that gives you a user-thrown value in case of Emscripten EH, and a
// WebAssembly.Exception object in case of Wasm EH. 'getExceptionMessage' takes
// the user-thrown value in case of Emscripten EH and the WebAssembly.Exception
// object in case of Wasm EH, meaning in both cases you can pass a caught
// exception directly to the function.
//
// When used with Wasm EH, this option additionally provides these functions in
// the JS library:
//
// - getCppExceptionTag: Returns the C++ tag
// - getCppExceptionThrownObjectFromWebAssemblyException:
//   Given an WebAssembly.Exception object, returns the actual user-thrown C++
//   object address in Wasm memory.
//
// Setting this option also adds refcount incrementing and decrementing
// functions ('incrementExceptionRefcount' and 'decrementExceptionRefcount') in
// the JS library because if you catch an exception from JS, you may need to
// manipulate the refcount manually to avoid memory leaks.
//
// See test_EXPORT_EXCEPTION_HANDLING_HELPERS in test/test_core.py for an
// example usage.
// [deprecated]
var EXPORT_EXCEPTION_HANDLING_HELPERS = false;

// When this is enabled, exceptions will contain stack traces and uncaught
// exceptions will display stack traces upon exiting. This defaults to true when
// ASSERTIONS is enabled. This option is for users who want exceptions' stack
// traces but do not want other overheads ASSERTIONS can incur.
// This option implies :ref:`EXPORT_EXCEPTION_HANDLING_HELPERS`.
// [link]
var EXCEPTION_STACK_TRACES = false;

// If true, emit instructions for the legacy Wasm exception handling proposal:
// https://github.com/WebAssembly/exception-handling/blob/main/proposals/exception-handling/legacy/Exceptions.md
// If false, emit instructions for the standardized exception handling proposal:
// https://github.com/WebAssembly/exception-handling/blob/main/proposals/exception-handling/Exceptions.md
// [compile+link]
var WASM_LEGACY_EXCEPTIONS = true;

// Whether to support async operations in the compiled code. This makes it
// possible to call JS functions from synchronous-looking code in C/C++.
//
// - 1 (default): Run binaryen's Asyncify pass to transform the code using
//   asyncify. This emits a normal wasm file in the end, so it works everywhere,
//   but it has a significant cost in terms of code size and speed.
//   See https://emscripten.org/docs/porting/asyncify.html
// - 2 (deprecated): Use ``-sJSPI`` instead.
//
// [link]
var ASYNCIFY = 0;

// Imports which can do an async operation, in addition to the default ones that
// emscripten defines like emscripten_sleep. If you add more you will need to
// mention them to here, or else they will not work (in :ref:`ASSERTIONS` builds
// an error will be shown).
// Note that this list used to contain the default ones, which meant that you
// had to list them when adding your own; the default ones are now added
// automatically.
// [link]
var ASYNCIFY_IMPORTS = [];

// Whether indirect calls can be on the stack during an unwind/rewind.
// If you know they cannot, then setting this can be extremely helpful, as
// otherwise asyncify must assume an indirect call can reach almost everywhere.
// [link]
var ASYNCIFY_IGNORE_INDIRECT = false;

// The size of the asyncify stack - the region used to store unwind/rewind
// info. This must be large enough to store the call stack and locals. If it is
// too small, you will see a wasm trap due to executing an "unreachable"
// instruction. In that case, you should increase this size.
// [link]
var ASYNCIFY_STACK_SIZE = 4096;

// If the Asyncify remove-list is provided, then the functions in it will not
// be instrumented even if it looks like they need to. This can be useful
// if you know things the whole-program analysis doesn't, like if you
// know certain indirect calls are safe and won't unwind. But if you
// get the list wrong things will break (and in a production build user
// input might reach code paths you missed during testing, so it's hard
// to know you got this right), so this is not recommended unless you
// really know what are doing, and need to optimize every bit of speed
// and size.
//
// The names in this list are names from the WebAssembly Names section. The
// wasm backend will emit those names in *human-readable* form instead of
// typical C++ mangling. For example, you should write ``Struct::func()``
// instead of ``_ZN6Struct4FuncEv``. C is also different from C++, as C
// names don't end with parameters; as a result foo(int) in C++ would appear
// as just foo in C (C++ has parameters because it needs to differentiate
// overloaded functions). You will see warnings in the console if a name in the
// list is missing (these are not errors because inlining etc. may cause
// changes which would mean a single list couldn't work for both -O0 and -O1
// builds, etc.). You can inspect the wasm binary to look for the actual names,
// either directly or using wasm-objdump or wasm-dis, etc.
//
// Simple ``*`` wildcard matching is supported.
//
// To avoid dealing with limitations in operating system shells or build system
// escaping, the following substitutions can be made:
//
// - ' ' -> ``.``,
// - ``&`` -> ``#``,
// - ``,`` -> ``?``.
//
// That is, the function `"foo(char const*, int&)"` can be inputted as
// `"foo(char.const*?.int#)"` on the command line instead.
//
// Note: Whitespace is part of the function signature! I.e.
// "foo(char const *, int &)" will not match "foo(char const*, int&)", and
// neither would "foo(const char*, int &)".
//
// [link]
var ASYNCIFY_REMOVE = [];

// Functions in the Asyncify add-list are added to the list of instrumented
// functions, that is, they will be instrumented even if otherwise asyncify
// thinks they don't need to be. As by default everything will be instrumented
// in the safest way possible, this is only useful if you use IGNORE_INDIRECT
// and use this list to fix up some indirect calls that *do* need to be
// instrumented.
//
// See :ref:`ASYNCIFY_REMOVE` about the names, including wildcard matching and
// character substitutions.
// [link]
var ASYNCIFY_ADD = [];

// If enabled, instrumentation status will be propagated from the add-list, ie.
// their callers, and their callers' callers, and so on. If disabled then all
// callers must be manually added to the add-list (like the only-list).
// [link]
var ASYNCIFY_PROPAGATE_ADD = true;

// If the Asyncify only-list is provided, then *only* the functions in the list
// will be instrumented. Like the remove-list, getting this wrong will break
// your application.
//
// See :ref:`ASYNCIFY_REMOVE` about the names, including wildcard matching and
// character substitutions.
// [link]
var ASYNCIFY_ONLY = [];

// If enabled will output which functions have been instrumented and why.
// [link]
var ASYNCIFY_ADVISE = false;

// Runtime debug logging from asyncify internals.
//
// - 1: Minimal logging.
// - 2: Verbose logging.
//
// [link]
var ASYNCIFY_DEBUG = 0;

// Deprecated, use JSPI_EXPORTS instead.
// [deprecated]
var ASYNCIFY_EXPORTS = [];

// Use VM support for the JavaScript Promise Integration proposal. This allows
// async operations to happen without the overhead of modifying the wasm. This
// is experimental at the moment while spec discussion is ongoing, see
// https://github.com/WebAssembly/js-promise-integration/ TODO: document which
// of the following flags are still relevant in this mode (e.g. IGNORE_INDIRECT
// etc. are not needed)
//
// [link]
var JSPI = 0;

// A list of exported module functions that will be asynchronous. Each export
// will return a ``Promise`` that will be resolved with the result. Any exports
// that will call an asynchronous import (listed in ``JSPI_IMPORTS``) must be
// included here.
//
// By default this includes ``main``.
// [link]
var JSPI_EXPORTS = [];


// A list of imported module functions that will potentially do asynchronous
// work. The imported function should return a ``Promise`` when doing
// asynchronous work.
//
// Note when using JS library files, the function can be marked with
// ``<function_name>_async:: true`` in the library instead of this setting.
// [link]
var JSPI_IMPORTS = [];

// Runtime elements that are exported on Module by default. We used to export
// quite a lot here, but have removed them all. You should use
// EXPORTED_RUNTIME_METHODS for things you want to export from the runtime.
// Note that the name may be slightly misleading, as this is for any JS library
// element, and not just methods. For example, we can export the FS object by
// having "FS" in this list.
// [link]
var EXPORTED_RUNTIME_METHODS = [];

// A list of incoming values on the Module object in JS that we care about. If
// a value is not in this list, then we don't emit code to check if you provide
// it on the Module object. For example, if
// you have this::
//
//   var Module = {
//     print: (x) => console.log('print: ' + x),
//     preRun: [() => console.log('pre run')]
//   };
//
// Then INCOMING_MODULE_JS_API must contain 'print' and 'preRun'; if it does not
// then we may not emit code to read and use that value. In other words, this
// option lets you set, statically at compile time, the list of which Module
// JS values you will be providing at runtime, so the compiler can better
// optimize.
//
// Setting this list to [], or at least a short and concise set of names you
// actually use, can be very useful for reducing code size. By default, the
// list contains a set of commonly used symbols.
//
// FIXME: should this just be  0  if we want everything?
// [link]
var INCOMING_MODULE_JS_API = [
  'ENVIRONMENT', 'GL_MAX_TEXTURE_IMAGE_UNITS', 'SDL_canPlayWithWebAudio',
  'SDL_numSimultaneouslyQueuedBuffers', 'INITIAL_MEMORY', 'wasmMemory', 'arguments',
  'buffer', 'canvas', 'doNotCaptureKeyboard', 'dynamicLibraries',
  'elementPointerLock', 'extraStackTrace', 'forcedAspectRatio',
  'instantiateWasm', 'keyboardListeningElement', 'freePreloadedMediaOnUse',
  'locateFile', 'mainScriptUrlOrBlob', 'mem',
  'monitorRunDependencies', 'noExitRuntime', 'noInitialRun', 'onAbort',
  'onExit', 'onFullScreen', 'onRuntimeInitialized', 'postMainLoop', 'postRun',
  'preInit', 'preMainLoop', 'preRun',
  'preinitializedWebGLContext', 'preloadPlugins',
  'print', 'printErr', 'setStatus', 'statusMessage', 'stderr',
  'stdin', 'stdout', 'thisProgram', 'wasm', 'wasmBinary', 'websocket'
];

// If set to nonzero, the provided virtual filesystem is treated
// case-insensitive, like Windows and macOS do. If set to 0, the VFS is
// case-sensitive, like on Linux.
// [link]
var CASE_INSENSITIVE_FS = false;

// If set to 0, does not build in any filesystem support. Useful if you are just
// doing pure computation, but not reading files or using any streams (including
// fprintf, and other stdio.h things) or anything related. The one exception is
// there is partial support for printf, and puts, hackishly.  The compiler will
// automatically set this if it detects that syscall usage (which is static)
// does not require a full filesystem. If you still want filesystem support, use
// FORCE_FILESYSTEM
// [link]
var FILESYSTEM = true;

// Makes full filesystem support be included, even if statically it looks like
// it is not used. For example, if your C code uses no files, but you include
// some JS that does, you might need this.
// [link]
var FORCE_FILESYSTEM = false;

// Enables support for the ``NODERAWFS`` filesystem backend. This is a special
// backend as it replaces all normal filesystem access with direct Node.js
// operations, without the need to do ``FS.mount()``, and this backend only
// works with Node.js. The initial working directory will be same as
// process.cwd() instead of VFS root directory.  Because this mode directly uses
// Node.js to access the real local filesystem on your OS, the code will not
// necessarily be portable between OSes - it will be as portable as a Node.js
// program would be, which means that differences in how the underlying OS
// handles permissions and errors and so forth may be noticeable.
//
// Enabling this setting will also enable :ref:`NODE_HOST_ENV` by default.
// [link]
var NODERAWFS = false;

// When running under Node, expose the underlying OS environment variables.
// This is similar to how ``NODERAWFS`` exposes the underlying FS.
// This setting gets enabled by default when ``NODERAWFS`` is enabled, but can
// also be controlled separately.
var NODE_HOST_ENV = false;

// This saves the compiled wasm module in a file with name
// ``$WASM_BINARY_NAME.$V8_VERSION.cached``
// and loads it on subsequent runs. This caches the compiled wasm code from
// v8 in node, which saves compiling on subsequent runs, making them start up
// much faster.
// The V8 version used in node is included in the cache name so that we don't
// try to load cached code from another version, which fails silently (it seems
// to load ok, but we do actually recompile).
//
// - The only version known to work for sure is node 12.9.1, as this has
//   regressed, see
//   https://github.com/nodejs/node/issues/18265#issuecomment-622971547
// - The default location of the .cached files is alongside the wasm binary,
//   as mentioned earlier. If that is in a read-only directory, you may need
//   to place them elsewhere. You can use the locateFile() hook to do so.
//
// [link]
var NODE_CODE_CACHING = false;

// Symbols that are explicitly exported. These symbols are kept alive through
// LLVM dead code elimination, and also made accessible outside of the
// generated code even after running closure compiler (on "Module").  Native
// symbols listed here require an ``_`` prefix.
//
// By default if this setting is not specified on the command line the
// ``_main`` function will be implicitly exported.  In :ref:`STANDALONE_WASM`
// mode the default export is ``__start`` (or ``__initialize`` if ``--no-entry``
// is specified).
//
// JS Library symbols can also be added to this list (without the leading `$`).
// [link]
var EXPORTED_FUNCTIONS = [];

// If true, we export all the symbols that are present in JS onto the Module
// object. This does not affect which symbols will be present - it does not
// prevent DCE or cause anything to be included in linking. It only does
// ``Module['X'] = X;``
// for all X that end up in the JS file. This is useful to export the JS
// library functions on Module, for things like dynamic linking.
// [link]
var EXPORT_ALL = false;

// If true, we export the symbols that are present in JS onto the Module
// object.
// It only does ``Module['X'] = X;``
var EXPORT_KEEPALIVE = true;

// Remembers the values of these settings, and makes them accessible
// through getCompilerSetting and emscripten_get_compiler_setting.
// To see what is retained, look for compilerSettings in the generated code.
// [link]
var RETAIN_COMPILER_SETTINGS = false;

// JS library elements (C functions implemented in JS) that we include by
// default.  If you want to make sure something is included by the JS compiler,
// add it here.  For example, if you do not use some ``emscripten_*`` C API call
// from C, but you want to call it from JS, add it here.
// Note that the name may be slightly misleading, as this is for any JS
// library element, and not just functions. For example, you can include the
// Browser object by adding "$Browser" to this list.
//
// If you want to both include and export a JS library symbol, it is enough to
// simply add it to EXPORTED_FUNCTIONS, without also adding it to
// DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.
// [link]
var DEFAULT_LIBRARY_FUNCS_TO_INCLUDE = [];

// Include all JS library functions instead of the sum of
// DEFAULT_LIBRARY_FUNCS_TO_INCLUDE + any functions used by the generated code.
// This is needed when dynamically loading (i.e. dlopen) modules that make use
// of runtime library functions that are not used in the main module.  Note that
// this only applies to js libraries, *not* C. You will need the main file to
// include all needed C libraries.  For example, if a module uses malloc or new,
// you will need to use those in the main file too to pull in malloc for use by
// the module.
// [link]
var INCLUDE_FULL_LIBRARY = false;

// A main module is a file compiled in a way that allows us to link it to
// a side module at runtime.
//
// - 1: Normal main module.
// - 2: DCE'd main module. We eliminate dead code normally. If a side
//   module needs something from main, it is up to you to make sure
//   it is kept alive.
//
// [compile+link]
var MAIN_MODULE = 0;

// Corresponds to MAIN_MODULE (also supports modes 1 and 2)
// [compile+link]
var SIDE_MODULE = 0;

// Deprecated, list shared libraries directly on the command line instead.
// [link]
// [deprecated]
var RUNTIME_LINKED_LIBS = [];

// If set to 1, this is a worker library, a special kind of library that is run
// in a worker. See emscripten.h
// [link]
var BUILD_AS_WORKER = false;

// If set to 1, compiles in a small stub main() in between the real main() which
// calls pthread_create() to run the application main() in a pthread.  This is
// something that applications can do manually as well if they wish, this option
// is provided as convenience.
//
// The pthread that main() runs on is a normal pthread in all ways, with the one
// difference that its stack size is the same as the main thread would normally
// have, that is, STACK_SIZE. This makes it easy to flip between
// PROXY_TO_PTHREAD and non-PROXY_TO_PTHREAD modes with main() always getting
// the same amount of stack.
//
// This proxies Module['canvas'], if present, and if OFFSCREENCANVAS_SUPPORT
// is enabled. This has to happen because this is the only chance - this browser
// main thread does the only pthread_create call that happens on
// that thread, so it's the only chance to transfer the canvas from there.
// [link]
var PROXY_TO_PTHREAD = false;

// If set to 1, this file can be linked with others, either as a shared library
// or as the main file that calls a shared library. To enable that, we will not
// internalize all symbols and cull the unused ones, in other words, we will not
// remove unused functions and globals, which might be used by another module we
// are linked with.
//
// MAIN_MODULE and SIDE_MODULE both imply this, so it not normally necessary
// to set this explicitly. Note that MAIN_MODULE and SIDE_MODULE mode 2 do
// *not* set this, so that we still do normal DCE on them, and in that case
// you must keep relevant things alive yourself using exporting.
// [compile+link]
// [deprecated]
var LINKABLE = false;

// Emscripten 'strict' build mode: Drop supporting any deprecated build options.
// Set the environment variable EMCC_STRICT=1 or pass -sSTRICT to test that a
// codebase builds nicely in forward compatible manner.
// Changes enabled by this:
//
//   - STRICT_JS is enabled.
//   - IGNORE_MISSING_MAIN is disabled.
//   - AUTO_JS_LIBRARIES is disabled.
//   - AUTO_NATIVE_LIBRARIES is disabled.
//   - DEFAULT_TO_CXX is disabled.
//   - ALLOW_UNIMPLEMENTED_SYSCALLS is disabled.
//   - INCOMING_MODULE_JS_API is set to empty by default.
// [compile+link]
var STRICT = false;

// Allow program to link with or without ``main`` symbol.
// If this is disabled then one must provide a ``main`` symbol or explicitly
// opt out by passing ``--no-entry`` or an EXPORTED_FUNCTIONS list that doesn't
// include ``_main``.
// [link]
var IGNORE_MISSING_MAIN = true;

// Add ``"use strict;"`` to generated JS
// [link]
var STRICT_JS = false;

// If set to 1, we will warn on any undefined symbols that are not resolved by
// the ``library_*.js`` files. Note that it is common in large projects to not
// implement everything, when you know what is not going to actually be called
// (and don't want to mess with the existing buildsystem), and functions might
// be implemented later on, say in --pre-js, so you may want to build with -s
// WARN_ON_UNDEFINED_SYMBOLS=0 to disable the warnings if they annoy you.  See
// also ERROR_ON_UNDEFINED_SYMBOLS.  Any undefined symbols that are listed in
// EXPORTED_FUNCTIONS will also be reported.
// [link]
var WARN_ON_UNDEFINED_SYMBOLS = true;

// If set to 1, we will give a link-time error on any undefined symbols (see
// WARN_ON_UNDEFINED_SYMBOLS). To allow undefined symbols at link time set this
// to 0, in which case if an undefined function is called a runtime error will
// occur.  Any undefined symbols that are listed in EXPORTED_FUNCTIONS will also
// be reported.
// [link]
var ERROR_ON_UNDEFINED_SYMBOLS = true;

// Use small chunk size for binary synchronous XHR's in Web Workers.  Used for
// testing.  See test_chunked_synchronous_xhr in runner.py and library.js.
// [link]
var SMALL_XHR_CHUNKS = false;

// By default we emit all code in a straightforward way into the output
// .js file. That means that if you load that in a script tag in a web
// page, it will use the global scope. With ``MODULARIZE`` set, we instead emit
// the code wrapped in an async function. This function returns a promise that
// resolves to a module instance once it is safe to run the compiled code
// (similar to the ``onRuntimeInitialized`` callback).
//
// The default name of the function is ``Module``, but can be changed using the
// ``EXPORT_NAME`` option. We recommend renaming it to a more typical name for a
// factory function, e.g. ``createModule``.
//
// You use the factory function like so::
//
//   const module = await EXPORT_NAME();
//
// or::
//
//   let module;
//   EXPORT_NAME().then(instance => {
//     module = instance;
//   });
//
//
// The factory function accepts 1 parameter, an object with default values for
// the module instance::
//
//   const module = await EXPORT_NAME({ option: value, ... });
//
// Note the parentheses - we are calling EXPORT_NAME in order to instantiate
// the module. This allows you to create multiple instances of the module.
//
// Note that in MODULARIZE mode we do *not* look for a global ``Module`` object
// for default values. Default values must be passed as a parameter to the
// factory function.
//
// The default .html shell file provided in MINIMAL_RUNTIME mode will create
// a singleton instance automatically, to run the application on the page.
// (Note that it does so without using the Promise API mentioned earlier, and
// so code for the Promise is not even emitted in the .js file if you tell
// emcc to emit an .html output.)
// The default .html shell file provided by traditional runtime mode is only
// compatible with MODULARIZE=0 mode, so when building with traditional
// runtime, you should provided your own html shell file to perform the
// instantiation when building with MODULARIZE=1. (For more details, see
// https://github.com/emscripten-core/emscripten/issues/7950)
//
// If you add --pre-js or --post-js files, they will be included inside
// the factory function with the rest of the emitted code in order to be
// optimized together with it.
//
// If you want to include code outside all of the generated code, including the
// factory function, you can use --extern-pre-js or --extern-post-js. While
// --pre-js and --post-js happen to do that in non-MODULARIZE mode, their
// intended usage is to add code that is optimized with the rest of the emitted
// code, allowing better dead code elimination and minification.
//
// Experimental Feature - Instance ES Modules:
//
// Note this feature is still under active development and is subject to change!
//
// To enable this feature use -sMODULARIZE=instance. Enabling this mode will
// produce an ES module that is a singleton with ES module exports. The
// module will export a default value that is an async init function and will
// also export named values that correspond to the Wasm exports and runtime
// exports. The init function must be called before any of the exports can be
// used. An example of using the module is below.
//
//   import init, { foo, bar } from "./my_module.mjs"
//   await init(optionalArguments);
//   foo();
//   bar();
//
// [link]
var MODULARIZE = false;

// Export using an ES6 Module export rather than a UMD export.  MODULARIZE must
// be enabled for ES6 exports and is implicitly enabled if not already set.
//
// This is implicitly enabled if the output suffix is set to 'mjs'.
//
// [link]
var EXPORT_ES6 = false;

// Global variable to export the module as for environments without a
// standardized module loading system (e.g. the browser and SM shell).
// [link]
var EXPORT_NAME = 'Module';

// When set to 0, we do not emit eval() and new Function(), which disables some
// functionality (causing runtime errors if attempted to be used), but allows
// the emitted code to be acceptable in places that disallow dynamic code
// execution (chrome packaged app, privileged firefox app, etc.). Pass this flag
// when developing an Emscripten application that is targeting a privileged or a
// certified execution environment, see Firefox Content Security Policy (CSP)
// webpage for details:
// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/script-src
// in particular the 'unsafe-eval' and 'wasm-unsafe-eval' policies.
//
// When this flag is set, the following features (linker flags) are unavailable:
//
//  - RELOCATABLE: the function loadDynamicLibrary would need to eval().
//
// and some features may fall back to slower code paths when they need to:
// Embind: uses eval() to jit functions for speed.
//
// Additionally, the following Emscripten runtime functions are unavailable when
// DYNAMIC_EXECUTION=0 is set, and an attempt to call them will throw an exception:
//
// - emscripten_run_script(),
// - emscripten_run_script_int(),
// - emscripten_run_script_string(),
// - dlopen(),
// - the functions ccall() and cwrap() are still available, but they are
//   restricted to only being able to call functions that have been exported in
//   the Module object in advance.
//
// When -sDYNAMIC_EXECUTION=2 is set, attempts to call to eval() are demoted to
// warnings instead of throwing an exception.
// [link]
var DYNAMIC_EXECUTION = 1;

// whether we are in the generate struct_info bootstrap phase
// [link]
var BOOTSTRAPPING_STRUCT_INFO = false;

// Add some calls to emscripten tracing APIs
// [compile+link]
var EMSCRIPTEN_TRACING = false;

// Specify the GLFW version that is being linked against.  Only relevant, if you
// are linking against the GLFW library.  Valid options are 2 for GLFW2 and 3
// for GLFW3.
// [link]
var USE_GLFW = 0;

// Whether to use compile code to WebAssembly. Set this to 0 to compile to JS
// instead of wasm.
//
// Specify -sWASM=2 to target both WebAssembly and JavaScript at the same time.
// In that build mode, two files a.wasm and a.wasm.js are produced, and at runtime
// the WebAssembly file is loaded if browser/shell supports it. Otherwise the
// .wasm.js fallback will be used.
//
// If WASM=2 is enabled and the browser fails to compile the WebAssembly module,
// the page will be reloaded in Wasm2JS mode.
// [link]
var WASM = 1;

// Indicates that we want to emit a wasm file that can run without JavaScript.
// The file will use standard APIs such as wasi as much as possible to achieve
// that.
//
// This option does not guarantee that the wasm can be used by itself - if you
// use APIs with no non-JS alternative, we will still use those (e.g., OpenGL
// at the time of writing this). This gives you the option to see which APIs
// are missing, and if you are compiling for a custom wasi embedding, to add
// those to your embedding.
//
// We may still emit JS with this flag, but the JS should only be a convenient
// way to run the wasm on the Web or in Node.js, and you can run the wasm by
// itself without that JS (again, unless you use APIs for which there is no
// non-JS alternative) in a wasm runtime like wasmer or wasmtime.
//
// Note that even without this option we try to use wasi etc. syscalls as much
// as possible. What this option changes is that we do so even when it means
// a tradeoff with JS size. For example, when this option is set we do not
// import the Memory - importing it is useful for JS, so that JS can start to
// use it before the wasm is even loaded, but in wasi and other wasm-only
// environments the expectation is to create the memory in the wasm itself.
// Doing so prevents some possible JS optimizations, so we only do it behind
// this flag.
//
// When this flag is set we do not legalize the JS interface, since the wasm is
// meant to run in a wasm VM, which can handle i64s directly. If we legalized it
// the wasm VM would not recognize the API. However, this means that the
// optional JS emitted won't run if you use a JS API with an i64. You can use
// the WASM_BIGINT option to avoid that problem by using BigInts for i64s which
// means we don't need to legalize for JS (but this requires a new enough JS
// VM).
//
// Standalone builds require a ``main`` entry point by default.  If you want to
// build a library (also known as a reactor) instead you can pass ``--no-entry``.
// [link]
var STANDALONE_WASM = false;

// Whether to ignore implicit traps when optimizing in binaryen.  Implicit
// traps are the traps that happen in a load that is out of bounds, or
// div/rem of 0, etc. With this option set, the optimizer assumes that loads
// cannot trap, and therefore that they have no side effects at all. This
// is *not* safe in general, as you may have a load behind a condition which
// ensures it it is safe; but if the load is assumed to not have side effects it
// could be executed unconditionally. For that reason this option is generally
// not useful on large and complex projects, but in a small and simple enough
// codebase it may help reduce code size a little bit.
// [link]
var BINARYEN_IGNORE_IMPLICIT_TRAPS = false;

// A comma-separated list of extra passes to run in the binaryen optimizer.
// Setting this does not override/replace the default passes. It is appended at
// the end of the list of passes.
// [link]
var BINARYEN_EXTRA_PASSES = "";

// Whether to compile the wasm asynchronously, which is more efficient and does
// not block the main thread. This is currently required for all but the
// smallest modules to run in chrome.
//
// (This option was formerly called BINARYEN_ASYNC_COMPILATION)
// [link]
var WASM_ASYNC_COMPILATION = true;

// If set to 1, the dynCall() and dynCall_sig() API is made available
// to caller.
// [link]
var DYNCALLS = false;

// WebAssembly integration with JavaScript BigInt. When enabled we don't need to
// legalize i64s into pairs of i32s, as the wasm VM will use a BigInt where an
// i64 is used.
// [link]
var WASM_BIGINT = true;

// WebAssembly defines a "producers section" which compilers and tools can
// annotate themselves in, and LLVM emits this by default.
// Emscripten will strip that out so that it is *not* emitted because it
// increases code size, and also some users may not want information
// about their tools to be included in their builds for privacy or security
// reasons, see
// https://github.com/WebAssembly/tool-conventions/issues/93.
// [link]
var EMIT_PRODUCERS_SECTION = false;

// Emits emscripten license info in the JS output.
// [link]
var EMIT_EMSCRIPTEN_LICENSE = false;

// Whether to legalize the JS FFI interfaces (imports/exports) by wrapping them
// to automatically demote i64 to i32 and promote f32 to f64. This is necessary
// in order to interface with JavaScript.  For non-web/non-JS embeddings,
// setting this to 0 may be desirable.
// [link]
// [deprecated]
var LEGALIZE_JS_FFI = true;

// Ports

// Specify the SDL version that is being linked against.
// 1, the default, is 1.3, which is implemented in JS
// 2 is a port of the SDL C code on emscripten-ports
// When AUTO_JS_LIBRARIES is set to 0 this defaults to 0 and SDL
// is not linked in.
// Alternate syntax for using the port: --use-port=sdl2
// [compile+link]
var USE_SDL = 0;

// Specify the SDL_gfx version that is being linked against. Must match USE_SDL
// [compile+link]
var USE_SDL_GFX = 0;

// Specify the SDL_image version that is being linked against. Must match USE_SDL
// [compile+link]
var USE_SDL_IMAGE = 1;

// Specify the SDL_ttf version that is being linked against. Must match USE_SDL
// [compile+link]
var USE_SDL_TTF = 1;

// Specify the SDL_net version that is being linked against. Must match USE_SDL
// [compile+link]
var USE_SDL_NET = 1;

// 1 = use icu from emscripten-ports
// Alternate syntax: --use-port=icu
// [compile+link]
var USE_ICU = false;

// 1 = use zlib from emscripten-ports
// Alternate syntax: --use-port=zlib
// [compile+link]
var USE_ZLIB = false;

// 1 = use bzip2 from emscripten-ports
// Alternate syntax: --use-port=bzip2
// [compile+link]
var USE_BZIP2 = false;

// 1 = use giflib from emscripten-ports
// Alternate syntax: --use-port=giflib
// [compile+link]
var USE_GIFLIB = false;

// 1 = use libjpeg from emscripten-ports
// Alternate syntax: --use-port=libjpeg
// [compile+link]
var USE_LIBJPEG = false;

// 1 = use libpng from emscripten-ports
// Alternate syntax: --use-port=libpng
// [compile+link]
var USE_LIBPNG = false;

// 1 = use Regal from emscripten-ports
// Alternate syntax: --use-port=regal
// [compile+link]
var USE_REGAL = false;

// 1 = use Boost headers from emscripten-ports
// Alternate syntax: --use-port=boost_headers
// [compile+link]
var USE_BOOST_HEADERS = false;

// 1 = use bullet from emscripten-ports
// Alternate syntax: --use-port=bullet
// [compile+link]
var USE_BULLET = false;

// 1 = use vorbis from emscripten-ports
// Alternate syntax: --use-port=vorbis
// [compile+link]
var USE_VORBIS = false;

// 1 = use ogg from emscripten-ports
// Alternate syntax: --use-port=ogg
// [compile+link]
var USE_OGG = false;

// 1 = use mpg123 from emscripten-ports
// Alternate syntax: --use-port=mpg123
// [compile+link]
var USE_MPG123 = false;

// 1 = use freetype from emscripten-ports
// Alternate syntax: --use-port=freetype
// [compile+link]
var USE_FREETYPE = false;

// Specify the SDL_mixer version that is being linked against.
// Doesn't *have* to match USE_SDL, but a good idea.
// [compile+link]
var USE_SDL_MIXER = 1;

// 1 = use harfbuzz from harfbuzz upstream
// Alternate syntax: --use-port=harfbuzz
// [compile+link]
var USE_HARFBUZZ = false;

// 3 = use cocos2d v3 from emscripten-ports
// Alternate syntax: --use-port=cocos2d
// [compile+link]
var USE_COCOS2D = 0;

// 1 = use libmodplug from emscripten-ports
// Alternate syntax: --use-port=libmodplug
// [compile+link]
var USE_MODPLUG = false;

// Formats to support in SDL2_image. Valid values: bmp, gif, lbm, pcx, png, pnm,
// tga, xcf, xpm, xv
// [compile+link]
var SDL2_IMAGE_FORMATS = [];

// Formats to support in SDL2_mixer. Valid values: ogg, mp3, mod, mid
// [compile+link]
var SDL2_MIXER_FORMATS = ["ogg"];

// 1 = use sqlite3 from emscripten-ports
// Alternate syntax: --use-port=sqlite3
// [compile+link]
var USE_SQLITE3 = false;

// If 1, target compiling a shared Wasm Memory.
// [compile+link]
var SHARED_MEMORY = false;

// Enables support for Wasm Workers.  Wasm Workers enable applications
// to create threads using a lightweight web-specific API that builds on top
// of Wasm SharedArrayBuffer + Atomics API.
// [compile+link]
var WASM_WORKERS = 0;

// If true, enables targeting Wasm Web Audio AudioWorklets. Check out the
// full documentation in site/source/docs/api_reference/wasm_audio_worklets.rst
//
// Note: The setting will implicitly add ``worklet`` to the :ref:`ENVIRONMENT`,
// (i.e. the resulting code and run in a worklet environment) but additionaly
// depends on ``WASM_WORKERS`` and Wasm SharedArrayBuffer to run new Audio
// Worklets.
// [link]
var AUDIO_WORKLET = 0;

// If true, enables utilizing k- and a-rate AudioParams based properties in
// Wasm Audio Worklet code. If false, AudioParams are not used. Set to false
// for a tiny improvement to code size and AudioWorklet CPU performance when
// audio synthesis is synchronized using custom WebAssembly Memory-based means.
// [link]
var AUDIO_WORKLET_SUPPORT_AUDIO_PARAMS = true;

// If true, enables deep debugging of Web Audio backend.
// [link]
var WEBAUDIO_DEBUG = 0;

// In web browsers, Workers cannot be created while the main browser thread
// is executing JS/Wasm code, but the main thread must regularly yield back
// to the browser event loop for Worker initialization to occur.
// This means that pthread_create() is essentially an asynchronous operation
// when called from the main browser thread, and the main thread must
// repeatedly yield back to the JS event loop in order for the thread to
// actually start.
// If your application needs to be able to synchronously create new threads,
// you can pre-create a pthread pool by specifying -sPTHREAD_POOL_SIZE=x,
// in which case the specified number of Workers will be preloaded into a pool
// before the application starts, and that many threads can then be available
// for synchronous creation.
// Note that this setting is a string, and will be emitted in the JS code
// (directly, with no extra quotes) so that if you set it to '5' then 5 workers
// will be used in the pool, and so forth. The benefit of this being a string
// is that you can set it to something like
// 'navigator.hardwareConcurrency' (which will use the number of cores the
// browser reports, and is how you can get exactly enough workers for a
// threadpool equal to the number of cores).
// [link] - affects generated JS runtime code at link time
var PTHREAD_POOL_SIZE = 0;

// Normally, applications can create new threads even when the pool is empty.
// When application breaks out to the JS event loop before trying to block on
// the thread via ``pthread_join`` or any other blocking primitive,
// an extra Worker will be created and the thread callback will be executed.
// However, breaking out to the event loop requires custom modifications to
// the code to adapt it to the Web, and not something that works for
// off-the-shelf apps. Those apps without any modifications are most likely
// to deadlock. This setting ensures that, instead of a risking a deadlock,
// they get a runtime EAGAIN error instead that can at least be gracefully
// handled from the C / C++ side.
// Values:
//
// - ``0`` - disable warnings on thread pool exhaustion
// - ``1`` - enable warnings on thread pool exhaustion (default)
// - ``2`` - make thread pool exhaustion a hard error
//
// [link]
var PTHREAD_POOL_SIZE_STRICT = 1;

// If your application does not need the ability to synchronously create
// threads, but it would still like to opportunistically speed up initial thread
// startup time by prewarming a pool of Workers, you can specify the size of
// the pool with -sPTHREAD_POOL_SIZE=x, but then also specify
// -sPTHREAD_POOL_DELAY_LOAD, which will cause the runtime to not wait up at
// startup for the Worker pool to finish loading. Instead, the runtime will
// immediately start up and the Worker pool will asynchronously spin up in
// parallel on the background. This can shorten the time that pthread_create()
// calls take to actually start a thread, but without actually slowing down
// main application startup speed. If PTHREAD_POOL_DELAY_LOAD=0 (default),
// then the runtime will wait for the pool to start up before running main().
// If you do need to synchronously wait on the created threads
// (e.g. via pthread_join), you must wait on the Module.pthreadPoolReady
// promise before doing so or you're very likely to run into deadlocks.
// [link] - affects generated JS runtime code at link time
var PTHREAD_POOL_DELAY_LOAD = false;

// Default stack size to use for newly created pthreads.  When not set, this
// defaults to STACK_SIZE (which in turn defaults to 64k).  Can also be set at
// runtime using pthread_attr_setstacksize().  Note that the wasm control flow
// stack is separate from this stack.  This stack only contains certain function
// local variables, such as those that have their addresses taken, or ones that
// are too large to fit as local vars in wasm code.
// [link]
var DEFAULT_PTHREAD_STACK_SIZE = 0;

// True when building with --threadprofiler
// [link]
var PTHREADS_PROFILING = false;

// It is dangerous to call pthread_join or pthread_cond_wait
// on the main thread, as doing so can cause deadlocks on the Web (and also
// it works using a busy-wait which is expensive). See
// https://emscripten.org/docs/porting/pthreads.html#blocking-on-the-main-browser-thread
// This may become set to 0 by default in the future; for now, this just
// warns in the console.
// [link]
var ALLOW_BLOCKING_ON_MAIN_THREAD = true;

// If true, add in debug traces for diagnosing pthreads related issues.
// [link]
var PTHREADS_DEBUG = false;

// This tries to evaluate code at compile time. The main use case is to eval
// global ctor functions, which are those that run before main(), but main()
// itself or parts of it can also be evalled. Evaluating code this way can avoid
// work at runtime, as it applies the results of the execution to memory and
// globals and so forth, "snapshotting" the wasm and then just running it from
// there when it is loaded.
//
// This will stop when it sees something it cannot eval at compile time, like a
// call to an import. When running with this option you will see logging that
// indicates what is evalled and where it stops.
//
// This optimization can either reduce or increase code size. If a small amount
// of code generates many changes in memory, for example, then overall size may
// increase.
//
// LLVM's GlobalOpt *almost* does this operation. It does in simple cases, where
// LLVM IR is not too complex for its logic to evaluate, but it isn't powerful
// enough for e.g. libc++ iostream ctors. It is just hard to do at the LLVM IR
// level - LLVM IR is complex and getting more complex, so this would require
// GlobalOpt to have a full interpreter, plus a way to write back into LLVM IR
// global objects.  At the wasm level, however, everything has been lowered
// into a simple low level, and we also just need to write bytes into an array,
// so this is easy for us to do. A further issue for LLVM is that it doesn't
// know that we will not link in further code, so it only tries to optimize
// ctors with lowest priority (while we do know explicitly if dynamic linking is
// enabled or not).
//
// If set to a value of 2, this also makes some "unsafe" assumptions,
// specifically that there is no input received while evalling ctors. That means
// we ignore args to main() as well as assume no environment vars are readable.
// This allows more programs to be optimized, but you need to make sure your
// program does not depend on those features - even just checking the value of
// argc can lead to problems.
//
// [link]
var EVAL_CTORS = 0;

// The default value or 1 means the generated code will use TextDecoder if
// available and fall back to custom decoder code when not available.
// If set to 2, we assume TextDecoder is present and usable, and do not emit
// any JS code to fall back if it is missing. Setting this zero to avoid even
// conditional usage of TextDecoder is no longer supported.
// Note: In -Oz builds, the default value of TEXTDECODER is set to 2, to save on
// code size (except when AUDIO_WORKLET is specified, or when `shell` is part
// of ENVIRONMENT since TextDecoder is not available in those environments).
// [link]
var TEXTDECODER = 1;

// Embind specific: If enabled, assume UTF-8 encoded data in std::string binding.
// Disable this to support binary data transfer.
// [link]
var EMBIND_STD_STRING_IS_UTF8 = true;

// Embind specific: If enabled, generate Embind's JavaScript invoker functions
// at compile time and include them in the JS output file. When used with
// DYNAMIC_EXECUTION=0 this allows exported bindings to be just as fast as
// DYNAMIC_EXECUTION=1 mode, but without the need for eval(). If there are many
// bindings the JS output size may be larger though.
var EMBIND_AOT = false;

// If set to 1, enables support for transferring canvases to pthreads and
// creating WebGL contexts in them, as well as explicit swap control for GL
// contexts. This needs browser support for the OffscreenCanvas specification.
// [link]
var OFFSCREENCANVAS_SUPPORT = false;

// If you are using PROXY_TO_PTHREAD with OFFSCREENCANVAS_SUPPORT, then specify
// here a comma separated list of CSS ID selectors to canvases to proxy over
// to the pthread at program startup, e.g. '#canvas1, #canvas2'.
// [link]
var OFFSCREENCANVASES_TO_PTHREAD = "#canvas";

// If set to 1, enables support for WebGL contexts to render to an offscreen
// render target, to avoid the implicit swap behavior of WebGL where exiting any
// event callback would automatically perform a "flip" to present rendered
// content on screen. When an Emscripten GL context has Offscreen Framebuffer
// enabled, a single frame can be composited from multiple event callbacks, and
// the swap function emscripten_webgl_commit_frame() is then explicitly called
// to present the rendered content on screen.
//
// The OffscreenCanvas feature also enables explicit GL frame swapping support,
// and also, -sOFFSCREEN_FRAMEBUFFER feature can be used to polyfill support
// for accessing WebGL in multiple threads in the absence of OffscreenCanvas
// support in browser, at the cost of some performance and latency.
// OffscreenCanvas and Offscreen Framebuffer support can be enabled at the same
// time, and allows one to utilize OffscreenCanvas where available, and to fall
// back to Offscreen Framebuffer otherwise.
// [link]
var OFFSCREEN_FRAMEBUFFER = false;

// If nonzero, Fetch API supports backing to IndexedDB. If 0, IndexedDB is not
// utilized. Set to 0 if IndexedDB support is not interesting for target
// application, to save a few kBytes.
// [link]
var FETCH_SUPPORT_INDEXEDDB = true;

// If nonzero, prints out debugging information in library_fetch.js
// [link]
var FETCH_DEBUG = false;

// If nonzero, enables emscripten_fetch API.
// [link]
var FETCH = false;

// Enables streaming fetched data when the fetch attribute
// EMSCRIPTEN_FETCH_STREAM_DATA is used. For streaming requests, the DOM Fetch
// API is used otherwise XMLHttpRequest is used.
// Both modes generally support the same API, but there are some key
// differences:
//
//  - XHR supports synchronous requests
//  - XHR supports overriding mime types
//  - Fetch supports streaming data using the 'onprogress' callback
//
// If set to a value of 2, only the DOM Fetch backend will be used. This should
// only be used in testing.
// [link]
var FETCH_STREAMING = 0;

// ATTENTION [WIP]: Experimental feature. Please use at your own risk.
// This will eventually replace the current JS file system implementation.
// If set to 1, uses new filesystem implementation.
// [link]
// [experimental]
var WASMFS = false;

// If set to 1, embeds all subresources in the emitted file as base64 string
// literals. Embedded subresources may include (but aren't limited to) wasm,
// asm.js, and static memory initialization code.
//
// When using code that depends on this option, your Content Security Policy may
// need to be updated. Specifically, embedding asm.js requires the script-src
// directive to allow 'unsafe-inline', and using a Worker requires the
// child-src directive to allow blob:. If you aren't using Content Security
// Policy, or your CSP header doesn't include either script-src or child-src,
// then you can safely ignore this warning.
//
// Note that SINGLE_FILE with binary encoding requires the HTML/JS files to be
// served with UTF-8 encoding. See the details on SINGLE_FILE_BINARY_ENCODE.
// [link]
var SINGLE_FILE = false;

// If true, binary Wasm content is encoded using a custom UTF-8 embedding
// instead of base64. This generates a smaller binary that compresses well.
// Set this to false to revert back to earlier base64 encoding if you run into
// issues with the binary encoding. (and please let us know of any such issues)
// If no issues arise, this option will permanently become the default in the
// future.
//
// NOTE: Binary encoding requires that the HTML/JS files are served with UTF-8
// encoding, and will not work with the default legacy Windows-1252 encoding
// that browsers might use on Windows. To enable UTF-8 encoding in a
// hand-crafted index.html file, apply any of:
// 1. Add `<meta charset="utf-8">` inside the <head> section of HTML, or
// 2. Add `<meta http-equiv="content-type" content="text/html; charset=UTF-8" />`` inside <head>, or
// 3. Add `<meta http-equiv="content-type" content="application/json; charset=utf-8" />` inside <head>
// (if using -o foo.js with SINGLE_FILE mode to build HTML+JS), or
// 4. pass the header `Content-Type: text/html; charset=utf-8` and/or header
// `Content-Type: application/javascript; charset=utf-8` when serving the
// relevant files that contain binary encoded content.
// If none of these are possible, disable binary encoding with
// -sSINGLE_FILE_BINARY_ENCODE=0 to fall back to base64 encoding.
// [link]
var SINGLE_FILE_BINARY_ENCODE = true;

// If set to 1, all JS libraries will be automatically available at link time.
// This gets set to 0 in STRICT mode (or with MINIMAL_RUNTIME) which mean you
// need to explicitly specify -lfoo.js in at link time in order to access
// library function in library_foo.js.
// [link]
var AUTO_JS_LIBRARIES = true;

// Like AUTO_JS_LIBRARIES but for the native libraries such as libgl, libal
// and libhtml5.   If this is disabled it is necessary to explicitly add
// e.g. -lhtml5 and also to first build the library using ``embuilder``.
// [link]
var AUTO_NATIVE_LIBRARIES = true;

// Specifies the oldest major version of Firefox to target. I.e. all Firefox
// versions >= MIN_FIREFOX_VERSION
// are desired to work. Pass -sMIN_FIREFOX_VERSION=majorVersion to drop support
// for Firefox versions older than majorVersion.
// Firefox 79 was released on 2020-07-28.
// MAX_INT (0x7FFFFFFF, or -1) specifies that target is not supported.
// Minimum supported value is 68 which was released on 2019-07-09 (see
// feature_matrix.py)
// [link]
var MIN_FIREFOX_VERSION = 79;

// Specifies the oldest version of desktop Safari to target. Version is encoded
// in MMmmVV, e.g. 70101 denotes Safari 7.1.1.
// Safari 14.1.0 was released on April 26, 2021, bundled with macOS 11.0 Big
// Sur and iOS 14.5.
// The previous default, Safari 12.0.0 was released on September 17, 2018,
// bundled with macOS 10.14.0 Mojave.
// NOTE: Emscripten is unable to produce code that would work in iOS 9.3.5 and
// older, i.e. iPhone 4s, iPad 2, iPad 3, iPad Mini 1, Pod Touch 5 and older,
// see https://github.com/emscripten-core/emscripten/pull/7191.
// Multithreaded Emscripten code will need Safari 12.2 (iPhone 5s+) at minimum,
// with support for DedicatedWorkerGlobalScope.name parameter.
// MAX_INT (0x7FFFFFFF, or -1) specifies that target is not supported.
// Minimum supported value is 120200 which was released on 2019-03-25 (see
// feature_matrix.py).
// [link]
var MIN_SAFARI_VERSION = 150000;

// Specifies the oldest version of Chrome. E.g. pass -sMIN_CHROME_VERSION=78 to
// drop support for Chrome 77 and older.
// This setting also applies to modern Chromium-based Edge, which shares version
// numbers with Chrome.
// Chrome 85 was released on 2020-08-25.
// MAX_INT (0x7FFFFFFF, or -1) specifies that target is not supported.
// Minimum supported value is 74, which was released on 2019-04-23 (see
// feature_matrix.py).
// [link]
var MIN_CHROME_VERSION = 85;

// Specifies minimum node version to target for the generated code.  This is
// distinct from the minimum version required to run the emscripten compiler.
// Version is encoded in MMmmVV, e.g. 181401 denotes Node 18.14.01.
// Minimum supported value is 180300, which was released 2022-05-18 (see
// feature_matrix.py). This version aligns with the version available in
// debian/stable (bookworm).
var MIN_NODE_VERSION = 180300;

// If true, uses minimal sized runtime without POSIX features, Module,
// preRun/preInit/etc., Emscripten built-in XHR loading or library_browser.js.
// Enable this setting to target the smallest code size possible.  Set
// MINIMAL_RUNTIME=2 to further enable even more code size optimizations. These
// opts are quite hacky, and work around limitations in Closure and other parts
// of the build system, so they may not work in all generated programs (But can
// be useful for really small programs).
//
// By default, no symbols will be exported on the ``Module`` object. In order
// to export kept alive symbols, please use ``-sEXPORT_KEEPALIVE=1``.
// [link]
var MINIMAL_RUNTIME = 0;

// If set to 1, MINIMAL_RUNTIME will utilize streaming WebAssembly compilation,
// where WebAssembly module is compiled already while it is being downloaded.
// In order for this to work, the web server MUST properly serve the .wasm file
// with a HTTP response header "Content-Type: application/wasm". If this HTTP
// header is not present, e.g. Firefox 73 will fail with an error message
// ``TypeError: Response has unsupported MIME type``
// and Chrome 78 will fail with an error message
// `Uncaught (in promise) TypeError: Failed to execute 'compile' on
// 'WebAssembly': Incorrect response MIME type. Expected 'application/wasm'`.
// If set to 0 (default), streaming WebAssembly compilation is disabled, which
// means that the WebAssembly Module will first be downloaded fully, and only
// then compilation starts.
// For large .wasm modules and production environments, this should be set to 1
// for faster startup speeds. However this setting is disabled by default
// since it requires server side configuration and for really small pages there
// is no observable difference (also has a ~100 byte impact to code size)
// This setting is only compatible with html output.
// [link]
var MINIMAL_RUNTIME_STREAMING_WASM_COMPILATION = false;

// If set to 1, MINIMAL_RUNTIME will utilize streaming WebAssembly instantiation,
// where WebAssembly module is compiled+instantiated already while it is being
// downloaded. Same restrictions/requirements apply as with
// MINIMAL_RUNTIME_STREAMING_WASM_COMPILATION.
// MINIMAL_RUNTIME_STREAMING_WASM_COMPILATION and
// MINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION cannot be simultaneously active.
// Which one of these two is faster depends on the size of the wasm module,
// the size of the JS runtime file, and the size of the preloaded data file
// to download, and the browser in question.
// [link]
var MINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION = false;

// If set to 'emscripten' or 'wasm', compiler supports setjmp() and longjmp().
// If set to 0, these APIs are not available.  If you are using C++ exceptions,
// but do not need setjmp()+longjmp() API, then you can set this to 0 to save a
// little bit of code size and performance when catching exceptions.
//
// 'emscripten': (default) Emscripten setjmp/longjmp handling using JavaScript
// 'wasm': setjmp/longjmp handling using Wasm EH instructions (experimental)
//
// - 0: No setjmp/longjmp handling
// - 1: Default setjmp/longjmp/handling, depending on the mode of exceptions.
//   'wasm' if '-fwasm-exceptions' is used, 'emscripten' otherwise.
//
// At compile time this enables the transformations needed for longjmp support
// at codegen time, while at link it allows linking in the library support.
// [compile+link]
var SUPPORT_LONGJMP = true;

// If set to 1, disables old deprecated HTML5 API event target lookup behavior.
// When enabled, there is no "Module.canvas" object, no magic "null" default
// handling, and DOM element 'target' parameters are taken to refer to CSS
// selectors, instead of referring to DOM IDs.
// [link]
var DISABLE_DEPRECATED_FIND_EVENT_TARGET_BEHAVIOR = true;

// Certain browser DOM API operations, such as requesting fullscreen mode
// transition or pointer lock require that the request originates from within
// a user initiated event, such as mouse click or keyboard press. Refactoring
// an application to follow this kind of program structure can be difficult, so
// HTML5_SUPPORT_DEFERRING_USER_SENSITIVE_REQUESTS allows transparent emulation
// of this by deferring such requests until a suitable event callback is
// generated. Set this to 0 to disable support for deferring to save code
// size if your application does not need support for deferred calls.
// [link]
var HTML5_SUPPORT_DEFERRING_USER_SENSITIVE_REQUESTS = true;

// Specifies whether the generated .html file is run through html-minifier. The
// set of optimization passes run by html-minifier depends on debug and
// optimization levels. In -g2 and higher, no minification is performed. In -g1,
// minification is done, but whitespace is retained. Minification requires at
// least -O1 or -Os to be used. Pass -sMINIFY_HTML=0 to explicitly choose to
// disable HTML minification altogether.
// [link]
var MINIFY_HTML = true;

// This option is no longer used. The appropriate shadow memory size is now
// calculated from INITIAL_MEMORY and MAXIMUM_MEMORY. Will be removed in a
// future release.
// [link]
var ASAN_SHADOW_SIZE = -1;

// List of path substitutions to apply in the "sources" field of the source map.
// Corresponds to the ``--prefix`` option used in ``tools/wasm-sourcemap.py``.
// Must be used with ``-gsource-map``.
//
// This setting allows to map path prefixes to the proper ones so that the final
// (possibly relative) URLs point to the correct locations :
// ``-sSOURCE_MAP_PREFIXES=/old/path=/new/path``
//
// [link]
var SOURCE_MAP_PREFIXES = [];

// Default to c++ mode even when run as ``emcc`` rather than ``emc++``.
// When this is disabled ``em++`` is required when linking C++ programs.
// Disabling this will match the behaviour of gcc/g++ and clang/clang++.
// [link]
var DEFAULT_TO_CXX = true;

// While LLVM's wasm32 has long double = float128, we don't support printing
// that at full precision by default. Instead we print as 64-bit doubles, which
// saves libc code size. You can flip this option on to get a libc with full
// long double printing precision.
// [link]
var PRINTF_LONG_DOUBLE = false;

// Setting this affects the path emitted in the wasm that refers to the DWARF
// file, in -gseparate-dwarf mode. This allows the debugging file to be hosted
// in a custom location.
// [link]
var SEPARATE_DWARF_URL = '';

// Emscripten runs wasm-ld to link, and in some cases will do further changes to
// the wasm afterwards, like running wasm-opt to optimize the binary in
// optimized builds. However, in some builds no wasm changes are necessary after
// link. This can make the entire link step faster, and can also be important
// for other reasons, like in debugging if the wasm is not modified then the
// DWARF info from LLVM is preserved (wasm-opt can rewrite it in some cases, but
// not in others like split-dwarf).
// When this flag is turned on, we error at link time if the build requires any
// changes to the wasm after link. This can be useful in testing, for example.
// Some example of features that require post-link wasm changes are:
//
// - Lowering i64 to i32 pairs at the JS boundary (See WASM_BIGINT)
// - Lowering sign-extension operation when targeting older browsers.
var ERROR_ON_WASM_CHANGES_AFTER_LINK = false;

// Abort on unhandled exceptions that occur when calling exported WebAssembly
// functions. This makes the program behave more like a native program where the
// OS would terminate the process and no further code can be executed when an
// unhandled exception (e.g. out-of-bounds memory access) happens.
// This will instrument all exported functions to catch thrown exceptions and
// call abort() when they happen. Once the program aborts any exported function
// calls will fail with a "program has already aborted" exception to prevent
// calls into code with a potentially corrupted program state.
// This adds a small fixed amount to code size in optimized builds and a slight
// overhead for the extra instrumented function indirection.  Enable this if you
// want Emscripten to handle unhandled exceptions nicely at the cost of a few
// bytes extra.
// Exceptions that occur within the ``main`` function are already handled via an
// alternative mechanism.
// [link]
var ABORT_ON_WASM_EXCEPTIONS = false;

// Build binaries that use as many WASI APIs as possible, and include additional
// JS support libraries for those APIs.  This allows emscripten to produce
// binaries that are more WASI compliant and also allows it to process and
// execute WASI binaries built with other SDKs (e.g.  wasi-sdk).
// This setting is experimental and subject to change or removal.
// Implies :ref:`STANDALONE_WASM`.
// [link]
// [experimental]
var PURE_WASI = false;

// Set to 1 to define the WebAssembly.Memory object outside of the wasm
// module.  By default the wasm module defines the memory and exports
// it to JavaScript.
// Use of the following settings will enable this settings since they
// depend on being able to define the memory in JavaScript:
//
// - -pthread
// - RELOCATABLE
// - ASYNCIFY_LAZY_LOAD_CODE
// - WASM2JS (WASM=0)
//
// [link]
var IMPORTED_MEMORY = false;

// Generate code to load split wasm modules.
// This option will automatically generate two wasm files as output, one
// with the ``.orig`` suffix and one without.  The default file (without
// the suffix) when run will generate instrumentation data that can later be
// fed into wasm-split (the binaryen tool).
// As well as this the generated JS code will contain helper functions
// to load split modules.
// [link]
// [experimental]
var SPLIT_MODULE = false;

// For MAIN_MODULE builds, automatically load any dynamic library dependencies
// on startup, before loading the main module.
var AUTOLOAD_DYLIBS = true;

// Link against stub implementations of unsupported/unimplemented syscalls. This
// allows programs that depend on these syscalls to be compiled, even though
// these functions will fail (or do nothing) at runtime.
// [link]
var ALLOW_UNIMPLEMENTED_SYSCALLS = true;

// Allow calls to Worker(...) and importScripts(...) to be Trusted Types
// compatible. Trusted Types is a Web Platform feature designed to mitigate DOM
// XSS by restricting the usage of DOM sink APIs.
// See https://w3c.github.io/webappsec-trusted-types/.
// [link]
var TRUSTED_TYPES = false;

// When targeting older browsers emscripten will sometimes require that
// polyfills be included in the output.  If you would prefer to take care of
// polyfilling yourself via some other mechanism you can prevent emscripten
// from generating these by passing ``-sNO_POLYFILL`` or ``-sPOLYFILL=0``
// With default browser targets emscripten does not need any polyfills so this
// settings is *only* needed when also explicitly targeting older browsers.
var POLYFILL = true;

// If non-zero, add tracing to core runtime functions.  Can be set to 2 for
// extra tracing (for example, tracing that occurs on each turn of the event
// loop or each user callback, which can flood the console).
// This setting is enabled by default if any of the following debugging settings
// are enabled:
//
// - PTHREADS_DEBUG
// - DYLINK_DEBUG
// - LIBRARY_DEBUG
// - GL_DEBUG
// - OPENAL_DEBUG
// - EXCEPTION_DEBUG
// - SYSCALL_DEBUG
// - WEBSOCKET_DEBUG
// - SOCKET_DEBUG
// - FETCH_DEBUG
//
// [link]
var RUNTIME_DEBUG = 0;

// Include JS library symbols that were previously part of the default runtime.
// Without this, such symbols can be made available by adding them to
// :ref:`DEFAULT_LIBRARY_FUNCS_TO_INCLUDE`, or via the dependencies of another
// JS library symbol.
var LEGACY_RUNTIME = false;

// User-defined functions to wrap with signature conversion, which take or
// return pointer arguments. Only affects ``MEMORY64=1`` builds, see
// ``create_pointer_conversion_wrappers`` in ``emscripten.py`` for details.
// Use ``_`` for non-pointer arguments, ``p`` for pointer/i53 arguments, and
// ``P`` for optional pointer/i53 values.
// Example use ``-sSIGNATURE_CONVERSIONS=someFunction:_p,anotherFunction:p``
// [link]
var SIGNATURE_CONVERSIONS = [];

// Experimental support for wasm source phase imports.
// This is only currently implemented in the pre-release/nightly version of
// node, and not yet supported by browsers.
// Requires EXPORT_ES6
// [link]
// [experimental]
var SOURCE_PHASE_IMPORTS = false;

// Experimental support for wasm ESM integration.
// Requires :ref:`EXPORT_ES6` and ``MODULARIZE=instance``
// [link]
// [experimental]
var WASM_ESM_INTEGRATION = false;

// Enable use of the JS arraybuffer-base64 API:
// https://github.com/tc39/proposal-arraybuffer-base64
// To run the resulting code currently requires passing `--js_base_64` to node
// or chrome.
// [experimental]
// [link]
var JS_BASE64_API = false;

// Enable support for GrowableSharedArrayBuffer.
// This features is only available behind a flag in recent versions of
// node/chrome.
// [experimental]
// [link]
var GROWABLE_ARRAYBUFFERS = false;

// If the emscripten-generated program is hosted on separate origin then
// starting new pthread worker can violate CSP rules.  Enabling
// CROSS_ORIGIN uses an inline worker to instead load the worker script
// indirectly using `importScripts`
var CROSS_ORIGIN = false;

// This setting changes the behaviour of the ``-shared`` flag.  The default
// setting of ``true`` means the ``-shared`` flag actually produces a normal
// object file (i.e. ``ld -r``).  Setting this to false will cause ``-shared``
// to behave like :ref:`SIDE_MODULE` and produce a dynamically linked
// library.
var FAKE_DYLIBS = true;

// Add a #! line to generated JS file and make it executable.  This is useful
// for building command line tools that run under node.
// This setting can also be set to a string value, in which case that string
// will be used as the #! command to embed in the generated file.
var EXECUTABLE = false;