[emcc] Refactor incompatible settings error reporting. NFC (#24853)

Author: sbc100

test/test_other.py

@@ -1652,10 +1652,10 @@ def test_minimal_runtime_export_all_modularize(self):
     self.assertContained('libf1\nlibf2\n', self.run_js('main.mjs'))
 
   def test_minimal_runtime_errors(self):
-    err = self.expect_fail([EMCC, test_file('hello_world.c'), '-sMINIMAL_RUNTIME_STREAMING_WASM_COMPILATION'])
+    err = self.expect_fail([EMCC, test_file('hello_world.c'), '-o', 'out.html', '-sMINIMAL_RUNTIME_STREAMING_WASM_COMPILATION'])
     self.assertContained('emcc: error: MINIMAL_RUNTIME_STREAMING_WASM_COMPILATION requires MINIMAL_RUNTIME', err)
 
-    err = self.expect_fail([EMCC, test_file('hello_world.c'), '-sMINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION'])
+    err = self.expect_fail([EMCC, test_file('hello_world.c'), '-o', 'our.html', '-sMINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION'])
     self.assertContained('emcc: error: MINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION requires MINIMAL_RUNTIME', err)
 
     err = self.expect_fail([EMCC, test_file('hello_world.c'), '-sMINIMAL_RUNTIME', '-sMINIMAL_RUNTIME_STREAMING_WASM_COMPILATION'])
@@ -13527,7 +13527,7 @@ def test_wasm2js_no_dylink(self):
     for arg in ('-sMAIN_MODULE', '-sSIDE_MODULE', '-sRELOCATABLE'):
       print(arg)
       err = self.expect_fail([EMCC, test_file('hello_world.c'), '-sWASM=0', arg])
-      self.assertContained('WASM2JS is not compatible with relocatable output', err)
+      self.assertContained('emcc: error: WASM2JS is not compatible with RELOCATABLE', err)
 
   def test_wasm2js_standalone(self):
     self.do_run_in_out_file_test('hello_world.c', cflags=['-sSTANDALONE_WASM', '-sWASM=0'])
@@ -14055,7 +14055,7 @@ def test_bad_export_name(self):
 
   def test_offset_convertor_plus_wasm2js(self):
     err = self.expect_fail([EMCC, '-sUSE_OFFSET_CONVERTER', '-sWASM=0', test_file('hello_world.c')])
-    self.assertContained('wasm2js is not compatible with USE_OFFSET_CONVERTER', err)
+    self.assertContained('emcc: error: WASM2JS is not compatible with USE_OFFSET_CONVERTER (see #14630)', err)
 
   def test_standard_library_mapping(self):
     # Test the `-l` flags on the command line get mapped the correct libraries variant
@@ -15255,7 +15255,7 @@ def test_standalone_settings(self):
     base_cmd = [EMCC, test_file('hello_world.c'), '-sSTANDALONE_WASM']
 
     err = self.expect_fail(base_cmd + ['-sMINIMAL_RUNTIME'])
-    self.assertContained('error: MINIMAL_RUNTIME reduces JS size, and is incompatible with STANDALONE_WASM which focuses on ignoring JS anyhow and being 100% wasm', err)
+    self.assertContained('emcc: error: STANDALONE_WASM is not compatible with MINIMAL_RUNTIME', err)
 
     err = self.expect_fail(base_cmd + ['-sMEMORY_GROWTH_GEOMETRIC_CAP=1mb'])
     self.assertContained('error: MEMORY_GROWTH_GEOMETRIC_CAP is not compatible with STANDALONE_WASM', err)

tools/link.py

@@ -650,13 +650,56 @@ def add_system_js_lib(lib):
   settings.JS_LIBRARIES.append(lib)
 
 
+def report_incompatible_settings():
+  # List of incompatible settings, of the form (SETTINGS_A, SETTING_B, OPTIONAL_REASON_FOR_INCOMPAT)
+  incompatible_settings = [
+    ('MINIMAL_RUNTIME', 'RELOCATABLE', None),
+    ('WASM2JS', 'RELOCATABLE', None),
+    ('MODULARIZE', 'PROXY_TO_WORKER', 'if you want to run in a worker with -sMODULARIZE, you likely want to do the worker side setup manually'),
+    ('MODULARIZE', 'NO_DECLARE_ASM_MODULE_EXPORTS', None),
+    ('EVAL_CTORS', 'WASM2JS', None),
+    ('EVAL_CTORS', 'RELOCATABLE', 'movable segments'),
+    # In Asyncify exports can be called more than once, and this seems to not
+    # work properly yet (see test_emscripten_scan_registers).
+    ('EVAL_CTORS', 'ASYNCIFY', None),
+    ('PTHREADS_PROFILING', 'NO_ASSERTIONS', 'only works with ASSERTIONS enabled'),
+    ('SOURCE_PHASE_IMPORTS', 'NO_EXPORT_ES6', None),
+    ('STANDALONE_WASM', 'MINIMAL_RUNTIME', None),
+    ('STRICT_JS', 'MODULARIZE', None),
+    ('STRICT_JS', 'EXPORT_ES6', None),
+    ('MINIMAL_RUNTIME_STREAMING_WASM_COMPILATION', 'MINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION', 'they are mutually exclusive'),
+    ('SEPARATE_DWARF', 'WASM2JS', 'as there is no wasm file'),
+    ('GL_SUPPORT_AUTOMATIC_ENABLE_EXTENSIONS', 'NO_GL_SUPPORT_SIMPLE_ENABLE_EXTENSIONS', None),
+    ('MODULARIZE', 'NODEJS_CATCH_REJECTION', None),
+    ('MODULARIZE', 'NODEJS_CATCH_EXIT', None),
+    ('WASM2JS', 'USE_OFFSET_CONVERTER', 'see #14630'),
+  ]
+
+  for a, b, reason in incompatible_settings:
+    invert_b = b.startswith('NO_')
+    if invert_b:
+      b = b[3:]
+
+    b_val = getattr(settings, b)
+    if invert_b:
+      b_val = not b_val
+
+    if getattr(settings, a) and b_val:
+      msg = f'{a} is not compatible with {b}'
+      if invert_b:
+        msg += '=0'
+      if reason:
+        msg += f' ({reason})'
+      exit_with_error(msg)
+
+
 @ToolchainProfiler.profile_block('linker_setup')
 def phase_linker_setup(options, linker_args):  # noqa: C901, PLR0912, PLR0915
   """Future modifications should consider refactoring to reduce complexity.
 
-  * The McCabe cyclomatiic complexity is currently 251 vs 10 recommended.
-  * There are currently 262 branches vs 12 recommended.
-  * There are currently 578 statements vs 50 recommended.
+  * The McCabe cyclomatiic complexity is currently 244 vs 10 recommended.
+  * There are currently 252 branches vs 12 recommended.
+  * There are currently 563 statements vs 50 recommended.
 
   To revalidate these numbers, run `ruff check --select=C901,PLR091`.
   """
@@ -717,8 +760,6 @@ def phase_linker_setup(options, linker_args):  # noqa: C901, PLR0912, PLR0915
     settings.MEMORYPROFILER = 1
 
   if settings.PTHREADS_PROFILING:
-    if not settings.ASSERTIONS:
-      exit_with_error('PTHREADS_PROFILING only works with ASSERTIONS enabled')
     options.post_js.append(utils.path_from_root('src/threadprofiler.js'))
     settings.REQUIRED_EXPORTS.append('emscripten_main_runtime_thread_id')
     # threadprofiler.js needs these library functions.
@@ -798,10 +839,6 @@ def phase_linker_setup(options, linker_args):  # noqa: C901, PLR0912, PLR0915
   if settings.GROWABLE_ARRAYBUFFERS:
     diagnostics.warning('experimental', '-sGROWABLE_ARRAYBUFFERS is still experimental and not yet supported in browsers')
 
-  if settings.SOURCE_PHASE_IMPORTS:
-    if not settings.EXPORT_ES6:
-      exit_with_error('SOURCE_PHASE_IMPORTS requires EXPORT_ES6')
-
   if settings.WASM_ESM_INTEGRATION:
     diagnostics.warning('experimental', '-sWASM_ESM_INTEGRATION is still experimental and not yet supported in browsers')
     default_setting('MODULARIZE', 'instance')
@@ -946,8 +983,6 @@ def limit_incoming_module_api():
       exit_with_error('MEMORY_GROWTH_LINEAR_STEP is not compatible with STANDALONE_WASM')
     if 'MEMORY_GROWTH_GEOMETRIC_CAP' in user_settings:
       exit_with_error('MEMORY_GROWTH_GEOMETRIC_CAP is not compatible with STANDALONE_WASM')
-    if settings.MINIMAL_RUNTIME:
-      exit_with_error('MINIMAL_RUNTIME reduces JS size, and is incompatible with STANDALONE_WASM which focuses on ignoring JS anyhow and being 100% wasm')
 
   # Note the exports the user requested
   building.user_requested_exports.update(settings.EXPORTED_FUNCTIONS)
@@ -998,9 +1033,6 @@ def limit_incoming_module_api():
       exit_with_error('EXPORT_ES6 requires MODULARIZE to be set')
     settings.MODULARIZE = 1
 
-  if settings.STRICT_JS and (settings.MODULARIZE or settings.EXPORT_ES6):
-    exit_with_error("STRICT_JS doesn't work with MODULARIZE or EXPORT_ES6")
-
   if not options.shell_path:
     # Minimal runtime uses a different default shell file
     if settings.MINIMAL_RUNTIME:
@@ -1051,11 +1083,8 @@ def limit_incoming_module_api():
   if settings.WASM == 2 and settings.SINGLE_FILE:
     exit_with_error('cannot have both WASM=2 and SINGLE_FILE enabled at the same time')
 
-  if settings.SEPARATE_DWARF and settings.WASM2JS:
-    exit_with_error('cannot have both SEPARATE_DWARF and WASM2JS at the same time (as there is no wasm file)')
-
-  if settings.MINIMAL_RUNTIME_STREAMING_WASM_COMPILATION and settings.MINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION:
-    exit_with_error('MINIMAL_RUNTIME_STREAMING_WASM_COMPILATION and MINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION are mutually exclusive!')
+  if settings.MINIMAL_RUNTIME_STREAMING_WASM_COMPILATION and options.oformat != OFormat.HTML:
+    exit_with_error('MINIMAL_RUNTIME_STREAMING_WASM_COMPILATION is only compatible with html output')
 
   if settings.MINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION and not settings.MINIMAL_RUNTIME:
     exit_with_error('MINIMAL_RUNTIME_STREAMING_WASM_INSTANTIATION requires MINIMAL_RUNTIME')
@@ -1141,10 +1170,6 @@ def limit_incoming_module_api():
         '__asyncify_data',
       ]
 
-    if settings.MINIMAL_RUNTIME:
-      exit_with_error('MINIMAL_RUNTIME is not compatible with relocatable output')
-    if settings.WASM2JS:
-      exit_with_error('WASM2JS is not compatible with relocatable output')
     # shared modules need memory utilities to allocate their memory
     settings.ALLOW_TABLE_GROWTH = 1
 
@@ -1231,8 +1256,6 @@ def limit_incoming_module_api():
     settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE += ['$setStackLimits']
 
   if settings.MODULARIZE:
-    if settings.PROXY_TO_WORKER:
-      exit_with_error('-sMODULARIZE is not compatible with --proxy-to-worker (if you want to run in a worker with -sMODULARIZE, you likely want to do the worker side setup manually)')
     # in MINIMAL_RUNTIME we may not need to emit the Promise code, as the
     # HTML output creates a singleton instance, and it does so without the
     # Promise. However, in Pthreads mode the Promise is used for worker
@@ -1251,8 +1274,6 @@ def limit_incoming_module_api():
   if settings.MODULARIZE:
     default_setting('NODEJS_CATCH_REJECTION', 0)
     default_setting('NODEJS_CATCH_EXIT', 0)
-    if settings.NODEJS_CATCH_REJECTION or settings.NODEJS_CATCH_EXIT:
-      exit_with_error('cannot use -sNODEJS_CATCH_REJECTION or -sNODEJS_CATCH_EXIT with -sMODULARIZE')
 
   if settings.POLYFILL:
     # Emscripten requires certain ES6+ constructs by default in library code
@@ -1284,9 +1305,6 @@ def limit_incoming_module_api():
   if settings.MIN_WEBGL_VERSION > settings.MAX_WEBGL_VERSION:
     exit_with_error('MIN_WEBGL_VERSION must be smaller or equal to MAX_WEBGL_VERSION!')
 
-  if not settings.GL_SUPPORT_SIMPLE_ENABLE_EXTENSIONS and settings.GL_SUPPORT_AUTOMATIC_ENABLE_EXTENSIONS:
-    exit_with_error('-sGL_SUPPORT_SIMPLE_ENABLE_EXTENSIONS=0 only makes sense with -sGL_SUPPORT_AUTOMATIC_ENABLE_EXTENSIONS=0!')
-
   if options.use_preload_plugins or len(options.preload_files) or len(options.embed_files):
     if settings.NODERAWFS:
       exit_with_error('--preload-file and --embed-file cannot be used with NODERAWFS which disables virtual filesystem')
@@ -1489,11 +1507,6 @@ def limit_incoming_module_api():
 
   set_initial_memory()
 
-  if settings.MODULARIZE and not settings.DECLARE_ASM_MODULE_EXPORTS:
-    # When MODULARIZE option is used, currently requires declaring all module exports
-    # individually - TODO: this could be optimized
-    exit_with_error('DECLARE_ASM_MODULE_EXPORTS=0 is not compatible with MODULARIZE')
-
   # When not declaring wasm module exports in outer scope one by one, disable minifying
   # wasm module export names so that the names can be passed directly to the outer scope.
   # Also, if using libexports.js API, disable minification so that the feature can work.
@@ -1533,17 +1546,6 @@ def limit_incoming_module_api():
     diagnostics.warning('emcc', 'SINGLE_FILE disables source map support (which requires a .map file)')
     settings.GENERATE_SOURCE_MAP = 0
 
-  if settings.EVAL_CTORS:
-    if settings.WASM2JS:
-      # code size/memory and correctness issues TODO
-      exit_with_error('EVAL_CTORS is not compatible with wasm2js yet')
-    elif settings.RELOCATABLE:
-      exit_with_error('EVAL_CTORS is not compatible with relocatable yet (movable segments)')
-    elif settings.ASYNCIFY:
-      # In Asyncify exports can be called more than once, and this seems to not
-      # work properly yet (see test_emscripten_scan_registers).
-      exit_with_error('EVAL_CTORS is not compatible with asyncify yet')
-
   if options.use_closure_compiler == 2 and not settings.WASM2JS:
     exit_with_error('closure compiler mode 2 assumes the code is asm.js, so not meaningful for wasm')
 
@@ -1590,8 +1592,6 @@ def limit_incoming_module_api():
       inc_initial_memory(50 * 1024 * 1024)
 
   if settings.USE_OFFSET_CONVERTER:
-    if settings.WASM2JS:
-      exit_with_error('wasm2js is not compatible with USE_OFFSET_CONVERTER (see #14630)')
     settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.append('$UTF8ArrayToString')
 
   if options.sanitize & UBSAN_SANITIZERS:
@@ -1885,6 +1885,8 @@ def get_full_import_name(name):
   if settings.USE_CLOSURE_COMPILER or not settings.MINIFY_WHITESPACE:
     settings.MAYBE_CLOSURE_COMPILER = 1
 
+  report_incompatible_settings()
+
   return target, wasm_target