Remove POLYFILL_OLD_MATH_FUNCTIONS setting

These polyfills are only needed on ancient browser versions that there
should be no need to support.

This change bumps out minimum required chrome version from 33 to 38.

ChangeLog.md

@@ -48,6 +48,9 @@ See docs/process.md for more on how version tagging works.
   `--post-js` files will now be delayed until after module creation and after
   `main` runs.  This matches the existing behaviour when using sync instantation
   (`-sWASM_ASYNC_COMPILATION=0`) but is an observable difference. (#23157)
+- The `POLYFILL_OLD_MATH_FUNCTIONS` setting was removed.  The browser versions
+  that require these polyfills are no longer supported by emscripten so the
+  polyfills should never be needed. (#23262)
 
 3.1.74 - 12/14/24
 -----------------

src/preamble.js

@@ -324,8 +324,6 @@ function addOnPostRun(cb) {
   __ATPOSTRUN__.unshift(cb);
 }
 
-#include "runtime_math.js"
-
 // A counter of dependencies for calling run(). If we need to
 // do asynchronous work before running, increment this and
 // decrement it. Incrementing must happen in a place like

src/preamble_minimal.js

@@ -85,7 +85,6 @@ var runtimeExited = false;
 var runtimeInitialized = false;
 #endif
 
-#include "runtime_math.js"
 #include "memoryprofiler.js"
 #include "runtime_exceptions.js"
 #include "runtime_debug.js"

test/other/codesize/test_codesize_hello_O0.gzsize

@@ -1 +1 @@
-8012
+7891

test/other/codesize/test_codesize_hello_O0.jssize

@@ -1 +1 @@
-21588
+21016

test/other/codesize/test_codesize_minimal_O0.gzsize

@@ -1 +1 @@
-6554
+6435

test/other/codesize/test_codesize_minimal_O0.jssize

@@ -1 +1 @@
-17637
+17061

test/other/test_unoptimized_code_size.js.size

@@ -1 +1 @@
-53887
+52851

test/other/test_unoptimized_code_size_no_asserts.js.size

@@ -1 +1 @@
-29086
+28642

test/other/test_unoptimized_code_size_strict.js.size

@@ -1 +1 @@
-52670
+51634

test/test_other.py

@@ -4908,20 +4908,6 @@ def test_precompiled_headers(self, suffix):
     output = self.run_js('a.out.js')
     self.assertContained('|5|', output)
 
-  def test_LEGACY_VM_SUPPORT(self):
-    # when modern features are lacking, we can polyfill them or at least warn
-    create_file('pre.js', 'Math.imul = undefined;')
-
-    def test(expected, opts):
-      print(opts)
-      self.run_process([EMCC, test_file('hello_world.c'), '--pre-js', 'pre.js'] + opts)
-      self.assertContained(expected, self.run_js('a.out.js', assert_returncode=0 if opts else NON_ZERO))
-
-    # when legacy is needed, we show an error indicating so
-    test('build with LEGACY_VM_SUPPORT', [])
-    # legacy + disabling wasm works
-    test('hello, world!', ['-sLEGACY_VM_SUPPORT', '-sWASM=0'])
-
   @crossplatform
   def test_on_abort(self):
     expected_output = 'Module.onAbort was called'

tools/link.py

@@ -1157,9 +1157,6 @@ def phase_linker_setup(options, state, newargs):  # noqa: C901, PLR0912, PLR0915
     if settings.MINIMAL_RUNTIME and options.oformat == OFormat.HTML and not settings.PTHREADS:
       settings.USE_READY_PROMISE = 0
 
-  if settings.WASM2JS and settings.LEGACY_VM_SUPPORT:
-    settings.POLYFILL_OLD_MATH_FUNCTIONS = 1
-
   check_browser_versions()
 
   if settings.MIN_NODE_VERSION >= 150000:
@@ -1202,10 +1199,6 @@ def phase_linker_setup(options, state, newargs):  # noqa: C901, PLR0912, PLR0915
     diagnostics.warning('transpile', '-sEXCEPTION_STACK_TRACES requires an engine that support ES6 classes.')
     settings.EXCEPTION_STACK_TRACES = 0
 
-  # Silently drop any individual backwards compatibility emulation flags that are known never to occur on browsers that support WebAssembly.
-  if not settings.WASM2JS:
-    settings.POLYFILL_OLD_MATH_FUNCTIONS = 0
-
   if settings.STB_IMAGE:
     state.append_link_flag('-lstb_image')
     settings.EXPORTED_FUNCTIONS += ['_stbi_load', '_stbi_load_from_memory', '_stbi_image_free']