Build-time error on use of emscripten_promise_any if Promise.any is not available

emcc.py

@@ -2420,6 +2420,14 @@ def phase_linker_setup(options, state, newargs):
   if settings.INCLUDE_FULL_LIBRARY and not settings.DISABLE_EXCEPTION_CATCHING:
     settings.EXPORTED_FUNCTIONS += ['___get_exception_message', '_free']
 
+  if settings.MEMORY64:
+    if settings.ASYNCIFY and settings.MEMORY64 == 1:
+      exit_with_error('MEMORY64=1 is not compatible with ASYNCIFY')
+    if not settings.DISABLE_EXCEPTION_CATCHING:
+      exit_with_error('MEMORY64 is not compatible with DISABLE_EXCEPTION_CATCHING=0')
+    # Any "pointers" passed to JS will now be i64's, in both modes.
+    settings.WASM_BIGINT = 1
+
   if settings.WASM_WORKERS:
     # TODO: After #15982 is resolved, these dependencies can be declared in library_wasm_worker.js
     #       instead of having to record them here.
@@ -2432,13 +2440,19 @@ def phase_linker_setup(options, state, newargs):
       settings.WASM_WORKER_FILE = unsuffixed(os.path.basename(target)) + '.ww.js'
     settings.JS_LIBRARIES.append((0, shared.path_from_root('src', 'library_wasm_worker.js')))
 
+  # Set min browser versions based on certain settings such as WASM_BIGINT,
+  # PTHREADS, AUDIO_WORKLET
+  # Such setting must be set before this point
+  feature_matrix.apply_min_browser_versions()
+
+  # TODO(sbc): Find make a generic way to expose the feature matrix to JS
+  # compiler rather then adding them all ad-hoc as internal settings
   settings.SUPPORTS_GLOBALTHIS = feature_matrix.caniuse(feature_matrix.Feature.GLOBALTHIS)
+  settings.SUPPORTS_PROMISE_ANY = feature_matrix.caniuse(feature_matrix.Feature.PROMISE_ANY)
   if not settings.BULK_MEMORY:
     settings.BULK_MEMORY = feature_matrix.caniuse(feature_matrix.Feature.BULK_MEMORY)
 
   if settings.AUDIO_WORKLET:
-    if not settings.SUPPORTS_GLOBALTHIS:
-      exit_with_error('Must target recent enough browser versions that will support globalThis in order to target Wasm Audio Worklets!')
     if settings.AUDIO_WORKLET == 1:
       settings.AUDIO_WORKLET_FILE = unsuffixed(os.path.basename(target)) + '.aw.js'
     settings.JS_LIBRARIES.append((0, shared.path_from_root('src', 'library_webaudio.js')))
@@ -2552,14 +2566,6 @@ def check_memory_setting(setting):
   if settings.SHARED_MEMORY or settings.RELOCATABLE or settings.ASYNCIFY_LAZY_LOAD_CODE or settings.WASM2JS:
     settings.IMPORTED_MEMORY = 1
 
-  if settings.MEMORY64:
-    if settings.ASYNCIFY and settings.MEMORY64 == 1:
-      exit_with_error('MEMORY64=1 is not compatible with ASYNCIFY')
-    if not settings.DISABLE_EXCEPTION_CATCHING:
-      exit_with_error('MEMORY64 is not compatible with DISABLE_EXCEPTION_CATCHING=0')
-    # Any "pointers" passed to JS will now be i64's, in both modes.
-    settings.WASM_BIGINT = 1
-
   if settings.WASM_BIGINT:
     settings.LEGALIZE_JS_FFI = 0
 
@@ -2900,8 +2906,6 @@ def get_full_import_name(name):
     if settings.WASM_EXCEPTIONS:
       settings.EXPORTED_FUNCTIONS += ['___cpp_exception', '___cxa_increment_exception_refcount', '___cxa_decrement_exception_refcount', '___thrown_object_from_unwind_exception']
 
-  feature_matrix.apply_min_browser_versions()
-
   if settings.SIDE_MODULE:
     # For side modules, we ignore all REQUIRED_EXPORTS that might have been added above.
     # They all come from either libc or compiler-rt.  The exception is __wasm_call_ctors

src/library_promise.js

@@ -216,7 +216,13 @@ mergeInto(LibraryManager.library, {
     return id;
   },
 
-  emscripten_promise_any__deps: ['$promiseMap', '$idsToPromises'],
+
+  emscripten_promise_any__deps: [
+    '$promiseMap', '$idsToPromises',
+#if !SUPPORTS_PROMISE_ANY && !INCLUDE_FULL_LIBRARY
+    () => error("emscripten_promise_any used, but Promise.any is not supported by the current runtime configuration (run with EMCC_DEBUG=1 in the env for more details)"),
+#endif
+  ],
   emscripten_promise_any: function(idBuf, errorBuf, size) {
     var promises = idsToPromises(idBuf, size);
 #if RUNTIME_DEBUG

src/settings_internal.js

@@ -175,6 +175,9 @@ var TARGET_NOT_SUPPORTED = 0x7FFFFFFF;
 // Used to track whether target environment supports the 'globalThis' attribute.
 var SUPPORTS_GLOBALTHIS = false;
 
+// Used to track whether target environment supports the 'Promise.any'.
+var SUPPORTS_PROMISE_ANY = false;
+
 // Wasm backend symbols that are considered system symbols and don't
 // have the normal C symbol name mangled applied (== prefix with an underscore)
 // (Also implicily on this list is any function that starts with string "dynCall_")

test/test_core.py

@@ -9761,6 +9761,14 @@ def test_main_reads_args(self):
 
   @requires_node
   def test_promise(self):
+    # This test depends on Promise.any, which in turn requires a modern target.  Check that it
+    # fails to even build without bumping the min versions:
+    err = self.expect_fail([EMCC, test_file('core/test_promise.c')])
+    self.assertContained('error: emscripten_promise_any used, but Promise.any is not supported by the current runtime configuration', err)
+    self.set_setting('MIN_NODE_VERSION', '150000')
+    self.set_setting('MIN_SAFARI_VERSION', '150000')
+    self.set_setting('MIN_FIREFOX_VERSION', '79')
+    self.set_setting('MIN_CHROME_VERSION', '85')
     self.do_core_test('test_promise.c')
 
 

tools/feature_matrix.py

@@ -22,6 +22,7 @@ class Feature(IntEnum):
   JS_BIGINT_INTEGRATION = auto()
   THREADS = auto()
   GLOBALTHIS = auto()
+  PROMISE_ANY = auto()
 
 
 default_features = {Feature.SIGN_EXT, Feature.MUTABLE_GLOBALS}
@@ -62,25 +63,44 @@ class Feature(IntEnum):
     'edge': 79,
     'firefox': 65,
     'safari': 120100,
-    # 'node': 120000
+    'node': 120000,
+  },
+  Feature.PROMISE_ANY: {
+    'chrome': 85,
+    'firefox': 79,
+    'safari': 140000,
+    'node': 150000,
   },
 }
 
 
 def caniuse(feature):
   min_versions = min_browser_versions[feature]
+
+  def report_missing(setting_name):
+    setting_value = getattr(settings, setting_name)
+    logger.debug(f'cannot use {feature.name} because {setting_name} is too old: {setting_value}')
+
   if settings.MIN_CHROME_VERSION < min_versions['chrome']:
+    report_missing('MIN_CHROME_VERSION')
     return False
   # For edge we just use the same version requirements as chrome since,
   # at least for modern versions of edge, they share version numbers.
   if settings.MIN_EDGE_VERSION < min_versions['chrome']:
+    report_missing('MIN_EDGE_VERSION')
     return False
   if settings.MIN_FIREFOX_VERSION < min_versions['firefox']:
+    report_missing('MIN_FIREFOX_VERSION')
     return False
   if settings.MIN_SAFARI_VERSION < min_versions['safari']:
+    report_missing('MIN_SAFARI_VERSION')
     return False
   # IE don't support any non-MVP features
   if settings.MIN_IE_VERSION != 0x7FFFFFFF:
+    report_missing('MIN_IE_VERSION')
+    return False
+  if 'node' in min_versions and settings.MIN_NODE_VERSION < min_versions['node']:
+    report_missing('MIN_NODE_VERSION')
     return False
   return True
 
@@ -112,3 +132,5 @@ def apply_min_browser_versions():
   if settings.PTHREADS:
     enable_feature(Feature.THREADS, 'pthreads')
     enable_feature(Feature.BULK_MEMORY, 'pthreads')
+  if settings.AUDIO_WORKLET:
+    enable_feature(Feature.GLOBALTHIS, 'AUDIO_WORKLET')