Skip to content

Make -gsource-map independent of name sections and JS minification #25238

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 13 commits into from
Sep 12, 2025
+43 −23
Merged

Make -gsource-map independent of name sections and JS minification #25238

Show file tree
Hide file tree
Changes from 6 commits
Commits
Show all changes
13 commits
Select commit Hold shift + click to select a range
081aad7
update tests
dschuff Sep 8, 2025
d45dbdf
fix namesec
dschuff Sep 9, 2025
031edff
fix test
dschuff Sep 9, 2025
5640b59
add changelog
dschuff Sep 9, 2025
0a13954
Merge branch 'main' into debug_g2
dschuff Sep 9, 2025
3d5720e
add PR link
dschuff Sep 9, 2025
7491915
Fix -g2 overriding gource-map when combining link+compile
dschuff Sep 10, 2025
04db06b
fix more tests using source maps + names
dschuff Sep 10, 2025
1479cb3
Merge branch 'main' into debug_g2
dschuff Sep 10, 2025
488a12e
add wasm-metadce to list of tools that support source map updates
dschuff Sep 11, 2025
963e3dd
move tests from documentation PR
dschuff Sep 11, 2025
beefb4d
Merge branch 'main' into debug_g2
dschuff Sep 11, 2025
ac9ee93
add extra sanitizer runtime test
dschuff Sep 11, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion test/test_browser.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -280,7 +280,7 @@ def test_sdl1_es6(self):
self.reftest('hello_world_sdl.c', 'htmltest.png', cflags=['-sUSE_SDL', '-lGL', '-sEXPORT_ES6'])

def test_emscripten_log(self):
self.btest_exit('test_emscripten_log.cpp', cflags=['-Wno-deprecated-pragma', '-gsource-map'])
self.btest_exit('test_emscripten_log.cpp', cflags=['-Wno-deprecated-pragma', '-gsource-map', '-g2'])
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Is this needed in the test now? If so maybe add a comment why? (I assume the source map is needed for logging, but not sure why -g2)

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The test expects both names and source lines in the output.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I see, thanks, so -g2 is for the names section.


@also_with_wasmfs
def test_preload_file(self):
Expand Down
14 changes: 9 additions & 5 deletions test/test_core.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -8979,27 +8979,31 @@ def test_sanitize_vptr(self):
])

@parameterized({
'g': ('-g', [
'g': (['-g'], [
".cpp:3:12: runtime error: reference binding to null pointer of type 'int'",
'in main',
]),
'g4': ('-gsource-map', [
'g2': (['-g2'], [
".cpp:3:12: runtime error: reference binding to null pointer of type 'int'",
'in main',
]),
'g4': (['-gsource-map', '-g2'], [
".cpp:3:12: runtime error: reference binding to null pointer of type 'int'",
'in main ',
'.cpp:3:8',
]),
})
@no_wasm2js('TODO: sanitizers in wasm2js')
@no_esm_integration('sanitizers do not support WASM_ESM_INTEGRATION')
def test_ubsan_full_stack_trace(self, g_flag, expected_output):
if g_flag == '-gsource-map':
def test_ubsan_full_stack_trace(self, g_flags, expected_output):
if '-gsource-map' in g_flags:
if self.is_wasm2js():
self.skipTest('wasm2js has no source map support')
elif self.get_setting('EVAL_CTORS'):
self.skipTest('EVAL_CTORS does not support source maps')

create_file('pre.js', 'Module.UBSAN_OPTIONS = "print_stacktrace=1";')
self.cflags += ['-fsanitize=null', g_flag, '--pre-js=pre.js']
self.cflags += ['-fsanitize=null', '--pre-js=pre.js'] + g_flags
self.set_setting('ALLOW_MEMORY_GROWTH')
self.do_runf('core/test_ubsan_full_null_ref.cpp',
assert_all=True, expected_output=expected_output)
Expand Down
7 changes: 6 additions & 1 deletion test/test_other.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3159,7 +3159,9 @@ def test_dwarf_sourcemap_names(self):
(['-g', '-gsource-map'], True, True, True),
(['-g2', '-gsource-map'], False, True, True),
(['-gsplit-dwarf', '-gsource-map'], True, True, True),
(['-Oz', '-gsource-map'], False, True, False),
(['-gsource-map', '-sERROR_ON_WASM_CHANGES_AFTER_LINK'], False, True, False),
(['-gsource-map', '-Og', '-sERROR_ON_WASM_CHANGES_AFTER_LINK'], False, True, False),
]:
print(flags, expect_dwarf, expect_sourcemap, expect_names)
self.emcc(test_file(source_file), flags, js_file)
Expand Down Expand Up @@ -9263,6 +9265,9 @@ def test_binaryen_debug(self):
(['-O2', '-g'], False, True, False),
(['-O2', '--closure=1'], True, False, True),
(['-O2', '--closure=1', '-g1'], True, True, True),
(['-O2', '--minify=0'], False, True, False),
(['-O2', '--profiling-funcs'], True, False, False),
(['-O2', '--profiling'], False, True, False),
]:
print(args, expect_clean_js, expect_whitespace_js, expect_closured)
delete_file('a.out.wat')
Expand Down Expand Up @@ -12383,7 +12388,7 @@ def test_lsan_leaks(self, ext, args):
def test_lsan_stack_trace(self, ext, regexes):
self.do_runf(
'other/test_lsan_leaks.' + ext,
cflags=['-fsanitize=leak', '-gsource-map'],
cflags=['-fsanitize=leak', '-gsource-map', '-g2'],
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Same question.

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Same answer: the test expects both names and line numbers.

regex=True,
assert_all=True,
assert_returncode=NON_ZERO,
Expand Down
2 changes: 1 addition & 1 deletion tools/building.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1232,7 +1232,7 @@ def run_binaryen_command(tool, infile, outfile=None, args=None, debug=False, std
# we must tell binaryen to update it
# TODO: all tools should support source maps; wasm-ctor-eval does not atm,
# for example
if settings.GENERATE_SOURCE_MAP and outfile and tool in ['wasm-opt', 'wasm-emscripten-finalize']:
if settings.GENERATE_SOURCE_MAP and outfile and tool in ['wasm-opt', 'wasm-emscripten-finalize', 'wasm-metadce']:
cmd += [f'--input-source-map={infile}.map']
cmd += [f'--output-source-map={outfile}.map']
shared.print_compiler_stage(cmd)
Expand Down
3 changes: 2 additions & 1 deletion tools/cmdline.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -368,7 +368,8 @@ def consume_arg_file():
settings.EMIT_NAME_SECTION = 1
# if we don't need to preserve LLVM debug info, do not keep this flag
# for clang
if settings.DEBUG_LEVEL < 3:
if (settings.DEBUG_LEVEL < 3 and not
(settings.GENERATE_SOURCE_MAP or settings.SEPARATE_DWARF)):
Copy link
Member

@aheejin aheejin Sep 11, 2025 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Why does something about settings.SEPARATE_DWARF has to change here? (What about split-dwarf and normal dwarf cases? Don't we need the same DEBUG_LEVEL for them?)

And has settings.SEPARATE_DWARF been set by this point? It looks we parse -gseparate-dwarf in line 385 and set settings.SEPARATE_DWARF in line 394 and 396.

Copy link
Member Author

@dschuff dschuff Sep 12, 2025 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Yeah, this logic is really tricky. Basically if you have -gsource-map and -g2 together at compile time (to get SM and names), then you set settings.GENERATE_SOURCE_MAP when you parse -gsource-map, and then when you parse -g2 it sets newargs[i] = '-g0' which turns off debug info entirely for the compile and breaks source maps.

Similarly with separate-dwarf which has the side effect of enabling debug info (rather than purely specifying that dwarf should be separated).

This change keeps that from happening, but I also think the fact that -g2 rounds to -g0 at compile time is a bug to fix in a future PR.

Copy link
Member

@aheejin aheejin Sep 12, 2025 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I'm not sure if I understand. And -gsource-map and -gseparate-dwarf are parsed below this line (-gsoure-map in line 399, -gseparate-dwarf in line 385) and settings.GENERATE_SOURCE_MAP and settings.SEPARATE_DWARF are set there, so I'm not sure how we can query these here. If this passes all tests that probably means I'm mistaken though.

Also where do we process -gsplit-dwarf?

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

the problem is when you have both flags you make 2 trips through this loop with gsource-map first. the first time it sets DEBUG_LEVEL to 3 and then the second time it sets it back to 2 and sets the 'g0' flag to clang, meaning no debug info at all.
-gsplit-dwarf falls into the else case at line 405.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Ah thanks, I forgot this code was within a loop...

newargs[i] = '-g0'
else:
# for 3+, report -g3 to clang as -g4 etc. are not accepted
Expand Down