[clang] [modules] Add err_main_in_named_module #146247

kish1n · 2025-06-28T23:36:34Z

As the issue said, main shouldn't be in any modules.

new diagnostic output:

/my/code/directory/main.cpp:3:1: warning: 'main' should not be attached to a named module; consider adding C++ language linkage [-Wmain]
    3 | int main() {
      | ^
      | extern "C++" 
1 warning generated.

github-actions · 2025-06-28T23:36:50Z

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llvmbot · 2025-06-28T23:37:13Z

@llvm/pr-subscribers-clang

Author: Ashwin Banwari (ashwinbanwari)

Changes

Close #146229

As the issue said, main shouldn't be in any modules.

New Error Output:

/my/code/directory/main.cpp:3:1: error: 'main' cannot be attached to a named module
    3 | int main() {
      | ^
1 error generated.

Full diff: https://github.com/llvm/llvm-project/pull/146247.diff

2 Files Affected:

(modified) clang/include/clang/Basic/DiagnosticSemaKinds.td (+2)
(modified) clang/lib/Sema/SemaDecl.cpp (+8)

diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index 5062505cf3c01..ce9017ded0087 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1062,6 +1062,8 @@ def err_constexpr_main : Error<
   "'main' is not allowed to be declared %select{constexpr|consteval}0">;
 def err_deleted_main : Error<"'main' is not allowed to be deleted">;
 def err_mainlike_template_decl : Error<"%0 cannot be a template">;
+def err_main_in_named_module
+    : Error<"'main' cannot be attached to a named module">;
 def err_main_returns_nonint : Error<"'main' must return 'int'">;
 def ext_main_returns_nonint : ExtWarn<"return type of 'main' is not 'int'">,
     InGroup<MainReturnType>;
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index e1cccf068b5aa..c4ddfda9f447f 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -12490,6 +12490,14 @@ void Sema::CheckMain(FunctionDecl *FD, const DeclSpec &DS) {
                                 : FixItHint());
       FD->setInvalidDecl(true);
     }
+
+    // In C++ [basic.start.main]p3, it is said a program attaching main to a
+    // named module is ill-formed.
+    if (FD->isInNamedModule()) {
+      Diag(FD->getTypeSpecStartLoc(), diag::err_main_in_named_module)
+          << FixItHint();
+      FD->setInvalidDecl(true);
+    }
   }
 
   // Treat protoless main() as nullary.

Mr-Anyone · 2025-06-29T03:13:24Z

You should add a test case and a release note for this patch to be accepted.

MikailBag · 2025-06-29T12:41:08Z

It seems that clang trunk warns on extern "C++" main, which is now allowed after P3618.

I think it will be helpful for the UX to land this change after that warning is fixed.

(Disclaimer: I'm not clang contributor, just clang user)

ChuanqiXu9 · 2025-06-30T01:44:48Z

I prefer a warning instead of hard error. There are already users who uses this.

ChuanqiXu9

LGTM. Thanks.

ChuanqiXu9 · 2025-06-30T07:37:09Z

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -1062,6 +1062,8 @@ def err_constexpr_main : Error<
  "'main' is not allowed to be declared %select{constexpr|consteval}0">;
 def err_deleted_main : Error<"'main' is not allowed to be deleted">;
 def err_mainlike_template_decl : Error<"%0 cannot be a template">;
+def warn_main_in_named_module


Let's add a warning option for it.

ChuanqiXu9 · 2025-06-30T07:37:23Z

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -1062,6 +1062,8 @@ def err_constexpr_main : Error<
  "'main' is not allowed to be declared %select{constexpr|consteval}0">;
 def err_deleted_main : Error<"'main' is not allowed to be deleted">;
 def err_mainlike_template_decl : Error<"%0 cannot be a template">;
+def warn_main_in_named_module
+    : Warning<"'main' should not be attached to a named module">;


And suggest them to wrap it into language linkage.

ChuanqiXu9 · 2025-06-30T08:28:55Z

clang/docs/ReleaseNotes.rst

@@ -650,6 +650,9 @@ Improvements to Clang's diagnostics
  #GH69470, #GH59391, #GH58172, #GH46215, #GH45915, #GH45891, #GH44490,
  #GH36703, #GH32903, #GH23312, #GH69874.

+- A warning is now emitted when ``main`` is attached to a named module,
+  which can be turned off with ``-Wno-main``. (#GH146247)


I prefer to change the warning name to Wmain-attached-to-named-modules. There were a lot examples declaring a warning with a warning name in place.

ChuanqiXu9 · 2025-06-30T08:47:02Z

Please use a new email name. We don't accept github.noreply mail.

github-actions · 2025-06-30T09:09:23Z

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llvm-ci · 2025-06-30T09:28:26Z

LLVM Buildbot has detected a new failure on builder openmp-offload-amdgpu-runtime-2 running on rocm-worker-hw-02 while building clang at step 7 "Add check check-clang".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/10/builds/8364

Here is the relevant piece of the build log for the reference

Step 7 (Add check check-clang) failure: test (failure)
******************** TEST 'Clang :: Driver/autocomplete.c' FAILED ********************
Exit Code: 1

Command Output (stdout):
--



-###	Print (but do not run) the commands to run for this compilation
--amdgpu-arch-tool=	Tool used for detecting AMD GPU arch in the system.
--analyze	Run the static analyzer
--analyzer-output	Static analyzer report output format (html|plist|plist-multi-file|plist-html|sarif|sarif-html|text).
--ansi	
--config-system-dir=	System directory for configuration files
--config-user-dir=	User directory for configuration files
--config=	Specify configuration file
--coverage	
--cuda-compile-host-device	Compile CUDA code for both host and device (default). Has no effect on non-CUDA compilations.
--cuda-device-only	Compile CUDA code for device only
--cuda-feature=	Manually specify the CUDA feature to use
--cuda-gpu-arch=	
--cuda-host-only	Compile CUDA code for host only. Has no effect on non-CUDA compilations.
--cuda-include-ptx=	Include PTX for the following GPU architecture (e.g. sm_35) or 'all'. May be specified more than once.
--cuda-noopt-device-debug	Enable device-side debug info generation. Disables ptxas optimizations.
--cuda-path-ignore-env	Ignore environment variables to detect CUDA installation
--cuda-path=	CUDA installation path
--driver-mode=	Set the driver mode to either 'gcc', 'g++', 'cpp', 'cl' or 'flang'
--dxv-path=	DXIL validator installation path
--embed-dir=	Add directory to embed search path
--emit-extension-symbol-graphs	Generate additional symbol graphs for extended modules.
--emit-static-lib	Enable linker job to emit a static library.
--end-no-unused-arguments	Start emitting warnings for unused driver arguments
--extract-api-ignores=	Comma separated list of files containing a new line separated list of API symbols to ignore when extracting API information.
--gcc-install-dir=	Use GCC installation in the specified directory. The directory ends with path components like 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Note: executables (e.g. ld) used by the compiler are not overridden by the selected GCC installation
--gcc-toolchain=	Specify a directory where Clang can find 'include' and 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Clang will use the GCC installation with the largest version
--gcc-triple=	Search for the GCC installation with the specified triple.
--gpu-bundle-output	Bundle output files of HIP device compilation
--gpu-instrument-lib=	Instrument device library for HIP, which is a LLVM bitcode containing __cyg_profile_func_enter and __cyg_profile_func_exit
--gpu-max-threads-per-block=	Default max threads per block for kernel launch bounds for HIP
--gpu-use-aux-triple-only	Prepare '-aux-triple' only without populating '-aux-target-cpu' and '-aux-target-feature'.
--help	Display available options
--help-hidden	Display help for hidden options
--hip-device-lib-path=	
--hip-device-lib=	HIP device library
--hip-link	Link clang-offload-bundler bundles for HIP
--hip-path=	HIP runtime installation path, used for finding HIP version and adding HIP include path.
--hip-version=	HIP version in the format of major.minor.patch
--hipspv-pass-plugin=	path to a pass plugin for HIP to SPIR-V passes.
--hipstdpar	Enable HIP acceleration for standard parallel algorithms
--hipstdpar-interpose-alloc	Replace all memory allocation / deallocation calls with hipManagedMalloc / hipFree equivalents
...

llvm-ci · 2025-06-30T09:29:11Z

LLVM Buildbot has detected a new failure on builder llvm-clang-x86_64-sie-ubuntu-fast running on sie-linux-worker while building clang at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/144/builds/28925

Here is the relevant piece of the build log for the reference

Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang :: Driver/autocomplete.c' FAILED ********************
Exit Code: 1

Command Output (stdout):
--



-###	Print (but do not run) the commands to run for this compilation
--amdgpu-arch-tool=	Tool used for detecting AMD GPU arch in the system.
--analyze	Run the static analyzer
--analyzer-output	Static analyzer report output format (html|plist|plist-multi-file|plist-html|sarif|sarif-html|text).
--ansi	
--config-system-dir=	System directory for configuration files
--config-user-dir=	User directory for configuration files
--config=	Specify configuration file
--coverage	
--cuda-compile-host-device	Compile CUDA code for both host and device (default). Has no effect on non-CUDA compilations.
--cuda-device-only	Compile CUDA code for device only
--cuda-feature=	Manually specify the CUDA feature to use
--cuda-gpu-arch=	
--cuda-host-only	Compile CUDA code for host only. Has no effect on non-CUDA compilations.
--cuda-include-ptx=	Include PTX for the following GPU architecture (e.g. sm_35) or 'all'. May be specified more than once.
--cuda-noopt-device-debug	Enable device-side debug info generation. Disables ptxas optimizations.
--cuda-path-ignore-env	Ignore environment variables to detect CUDA installation
--cuda-path=	CUDA installation path
--driver-mode=	Set the driver mode to either 'gcc', 'g++', 'cpp', 'cl' or 'flang'
--dxv-path=	DXIL validator installation path
--embed-dir=	Add directory to embed search path
--emit-extension-symbol-graphs	Generate additional symbol graphs for extended modules.
--emit-static-lib	Enable linker job to emit a static library.
--end-no-unused-arguments	Start emitting warnings for unused driver arguments
--extract-api-ignores=	Comma separated list of files containing a new line separated list of API symbols to ignore when extracting API information.
--gcc-install-dir=	Use GCC installation in the specified directory. The directory ends with path components like 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Note: executables (e.g. ld) used by the compiler are not overridden by the selected GCC installation
--gcc-toolchain=	Specify a directory where Clang can find 'include' and 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Clang will use the GCC installation with the largest version
--gcc-triple=	Search for the GCC installation with the specified triple.
--gpu-bundle-output	Bundle output files of HIP device compilation
--gpu-instrument-lib=	Instrument device library for HIP, which is a LLVM bitcode containing __cyg_profile_func_enter and __cyg_profile_func_exit
--gpu-max-threads-per-block=	Default max threads per block for kernel launch bounds for HIP
--gpu-use-aux-triple-only	Prepare '-aux-triple' only without populating '-aux-target-cpu' and '-aux-target-feature'.
--help	Display available options
--help-hidden	Display help for hidden options
--hip-device-lib-path=	
--hip-device-lib=	HIP device library
--hip-link	Link clang-offload-bundler bundles for HIP
--hip-path=	HIP runtime installation path, used for finding HIP version and adding HIP include path.
--hip-version=	HIP version in the format of major.minor.patch
--hipspv-pass-plugin=	path to a pass plugin for HIP to SPIR-V passes.
--hipstdpar	Enable HIP acceleration for standard parallel algorithms
--hipstdpar-interpose-alloc	Replace all memory allocation / deallocation calls with hipManagedMalloc / hipFree equivalents
...

kish1n · 2025-06-30T09:42:31Z

It seems I need to add the line // WARNING-NEXT: -Wmain-attached-to-named-module on this line to fix the autocomplete test.

What is the process to amend this PR?

llvm-ci · 2025-06-30T09:44:01Z

LLVM Buildbot has detected a new failure on builder llvm-clang-aarch64-darwin running on doug-worker-4 while building clang at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/190/builds/22459

Here is the relevant piece of the build log for the reference

Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang :: Driver/autocomplete.c' FAILED ********************
Exit Code: 1

Command Output (stdout):
--



-###	Print (but do not run) the commands to run for this compilation
--amdgpu-arch-tool=	Tool used for detecting AMD GPU arch in the system.
--analyze	Run the static analyzer
--analyzer-output	Static analyzer report output format (html|plist|plist-multi-file|plist-html|sarif|sarif-html|text).
--ansi	
--config-system-dir=	System directory for configuration files
--config-user-dir=	User directory for configuration files
--config=	Specify configuration file
--coverage	
--cuda-compile-host-device	Compile CUDA code for both host and device (default). Has no effect on non-CUDA compilations.
--cuda-device-only	Compile CUDA code for device only
--cuda-feature=	Manually specify the CUDA feature to use
--cuda-gpu-arch=	
--cuda-host-only	Compile CUDA code for host only. Has no effect on non-CUDA compilations.
--cuda-include-ptx=	Include PTX for the following GPU architecture (e.g. sm_35) or 'all'. May be specified more than once.
--cuda-noopt-device-debug	Enable device-side debug info generation. Disables ptxas optimizations.
--cuda-path-ignore-env	Ignore environment variables to detect CUDA installation
--cuda-path=	CUDA installation path
--driver-mode=	Set the driver mode to either 'gcc', 'g++', 'cpp', 'cl' or 'flang'
--dxv-path=	DXIL validator installation path
--embed-dir=	Add directory to embed search path
--emit-extension-symbol-graphs	Generate additional symbol graphs for extended modules.
--emit-static-lib	Enable linker job to emit a static library.
--end-no-unused-arguments	Start emitting warnings for unused driver arguments
--extract-api-ignores=	Comma separated list of files containing a new line separated list of API symbols to ignore when extracting API information.
--gcc-install-dir=	Use GCC installation in the specified directory. The directory ends with path components like 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Note: executables (e.g. ld) used by the compiler are not overridden by the selected GCC installation
--gcc-toolchain=	Specify a directory where Clang can find 'include' and 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Clang will use the GCC installation with the largest version
--gcc-triple=	Search for the GCC installation with the specified triple.
--gpu-bundle-output	Bundle output files of HIP device compilation
--gpu-instrument-lib=	Instrument device library for HIP, which is a LLVM bitcode containing __cyg_profile_func_enter and __cyg_profile_func_exit
--gpu-max-threads-per-block=	Default max threads per block for kernel launch bounds for HIP
--gpu-use-aux-triple-only	Prepare '-aux-triple' only without populating '-aux-target-cpu' and '-aux-target-feature'.
--help	Display available options
--help-hidden	Display help for hidden options
--hip-device-lib-path=	
--hip-device-lib=	HIP device library
--hip-link	Link clang-offload-bundler bundles for HIP
--hip-path=	HIP runtime installation path, used for finding HIP version and adding HIP include path.
--hip-version=	HIP version in the format of major.minor.patch
--hipspv-pass-plugin=	path to a pass plugin for HIP to SPIR-V passes.
--hipstdpar	Enable HIP acceleration for standard parallel algorithms
--hipstdpar-interpose-alloc	Replace all memory allocation / deallocation calls with hipManagedMalloc / hipFree equivalents
...

jplehr · 2025-06-30T09:45:19Z

It seems I need to add the line // WARNING-NEXT: -Wmain-attached-to-named-module on this line to fix the autocomplete test.

What is the process to amend this PR?

I think you can open a new PR that fixes the issue.

llvm-ci · 2025-06-30T10:28:02Z

LLVM Buildbot has detected a new failure on builder premerge-monolithic-linux running on premerge-linux-1 while building clang at step 7 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/153/builds/36443

Here is the relevant piece of the build log for the reference

Step 7 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang :: Driver/autocomplete.c' FAILED ********************
Exit Code: 1

Command Output (stdout):
--



-###	Print (but do not run) the commands to run for this compilation
--amdgpu-arch-tool=	Tool used for detecting AMD GPU arch in the system.
--analyze	Run the static analyzer
--analyzer-output	Static analyzer report output format (html|plist|plist-multi-file|plist-html|sarif|sarif-html|text).
--ansi	
--config-system-dir=	System directory for configuration files
--config-user-dir=	User directory for configuration files
--config=	Specify configuration file
--coverage	
--cuda-compile-host-device	Compile CUDA code for both host and device (default). Has no effect on non-CUDA compilations.
--cuda-device-only	Compile CUDA code for device only
--cuda-feature=	Manually specify the CUDA feature to use
--cuda-gpu-arch=	
--cuda-host-only	Compile CUDA code for host only. Has no effect on non-CUDA compilations.
--cuda-include-ptx=	Include PTX for the following GPU architecture (e.g. sm_35) or 'all'. May be specified more than once.
--cuda-noopt-device-debug	Enable device-side debug info generation. Disables ptxas optimizations.
--cuda-path-ignore-env	Ignore environment variables to detect CUDA installation
--cuda-path=	CUDA installation path
--driver-mode=	Set the driver mode to either 'gcc', 'g++', 'cpp', 'cl' or 'flang'
--dxv-path=	DXIL validator installation path
--embed-dir=	Add directory to embed search path
--emit-extension-symbol-graphs	Generate additional symbol graphs for extended modules.
--emit-static-lib	Enable linker job to emit a static library.
--end-no-unused-arguments	Start emitting warnings for unused driver arguments
--extract-api-ignores=	Comma separated list of files containing a new line separated list of API symbols to ignore when extracting API information.
--gcc-install-dir=	Use GCC installation in the specified directory. The directory ends with path components like 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Note: executables (e.g. ld) used by the compiler are not overridden by the selected GCC installation
--gcc-toolchain=	Specify a directory where Clang can find 'include' and 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Clang will use the GCC installation with the largest version
--gcc-triple=	Search for the GCC installation with the specified triple.
--gpu-bundle-output	Bundle output files of HIP device compilation
--gpu-instrument-lib=	Instrument device library for HIP, which is a LLVM bitcode containing __cyg_profile_func_enter and __cyg_profile_func_exit
--gpu-max-threads-per-block=	Default max threads per block for kernel launch bounds for HIP
--gpu-use-aux-triple-only	Prepare '-aux-triple' only without populating '-aux-target-cpu' and '-aux-target-feature'.
--help	Display available options
--help-hidden	Display help for hidden options
--hip-device-lib-path=	
--hip-device-lib=	HIP device library
--hip-link	Link clang-offload-bundler bundles for HIP
--hip-path=	HIP runtime installation path, used for finding HIP version and adding HIP include path.
--hip-version=	HIP version in the format of major.minor.patch
--hipspv-pass-plugin=	path to a pass plugin for HIP to SPIR-V passes.
--hipstdpar	Enable HIP acceleration for standard parallel algorithms
--hipstdpar-interpose-alloc	Replace all memory allocation / deallocation calls with hipManagedMalloc / hipFree equivalents
...

ChuanqiXu9 · 2025-06-30T10:57:32Z

FWIW, I fixed it in 5186d4a to avoid affecting more people longer.

llvm-ci · 2025-06-30T11:39:20Z

LLVM Buildbot has detected a new failure on builder clang-x86_64-debian-fast running on gribozavr4 while building clang at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/56/builds/29711

Here is the relevant piece of the build log for the reference

Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang :: Driver/autocomplete.c' FAILED ********************
Exit Code: 1

Command Output (stdout):
--



-###	Print (but do not run) the commands to run for this compilation
--amdgpu-arch-tool=	Tool used for detecting AMD GPU arch in the system.
--analyze	Run the static analyzer
--analyzer-output	Static analyzer report output format (html|plist|plist-multi-file|plist-html|sarif|sarif-html|text).
--ansi	
--config-system-dir=	System directory for configuration files
--config-user-dir=	User directory for configuration files
--config=	Specify configuration file
--coverage	
--cuda-compile-host-device	Compile CUDA code for both host and device (default). Has no effect on non-CUDA compilations.
--cuda-device-only	Compile CUDA code for device only
--cuda-feature=	Manually specify the CUDA feature to use
--cuda-gpu-arch=	
--cuda-host-only	Compile CUDA code for host only. Has no effect on non-CUDA compilations.
--cuda-include-ptx=	Include PTX for the following GPU architecture (e.g. sm_35) or 'all'. May be specified more than once.
--cuda-noopt-device-debug	Enable device-side debug info generation. Disables ptxas optimizations.
--cuda-path-ignore-env	Ignore environment variables to detect CUDA installation
--cuda-path=	CUDA installation path
--driver-mode=	Set the driver mode to either 'gcc', 'g++', 'cpp', 'cl' or 'flang'
--dxv-path=	DXIL validator installation path
--embed-dir=	Add directory to embed search path
--emit-extension-symbol-graphs	Generate additional symbol graphs for extended modules.
--emit-static-lib	Enable linker job to emit a static library.
--end-no-unused-arguments	Start emitting warnings for unused driver arguments
--extract-api-ignores=	Comma separated list of files containing a new line separated list of API symbols to ignore when extracting API information.
--gcc-install-dir=	Use GCC installation in the specified directory. The directory ends with path components like 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Note: executables (e.g. ld) used by the compiler are not overridden by the selected GCC installation
--gcc-toolchain=	Specify a directory where Clang can find 'include' and 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Clang will use the GCC installation with the largest version
--gcc-triple=	Search for the GCC installation with the specified triple.
--gpu-bundle-output	Bundle output files of HIP device compilation
--gpu-instrument-lib=	Instrument device library for HIP, which is a LLVM bitcode containing __cyg_profile_func_enter and __cyg_profile_func_exit
--gpu-max-threads-per-block=	Default max threads per block for kernel launch bounds for HIP
--gpu-use-aux-triple-only	Prepare '-aux-triple' only without populating '-aux-target-cpu' and '-aux-target-feature'.
--help	Display available options
--help-hidden	Display help for hidden options
--hip-device-lib-path=	
--hip-device-lib=	HIP device library
--hip-link	Link clang-offload-bundler bundles for HIP
--hip-path=	HIP runtime installation path, used for finding HIP version and adding HIP include path.
--hip-version=	HIP version in the format of major.minor.patch
--hipspv-pass-plugin=	path to a pass plugin for HIP to SPIR-V passes.
--hipstdpar	Enable HIP acceleration for standard parallel algorithms
--hipstdpar-interpose-alloc	Replace all memory allocation / deallocation calls with hipManagedMalloc / hipFree equivalents
...

llvm-ci · 2025-06-30T11:46:30Z

LLVM Buildbot has detected a new failure on builder llvm-x86_64-debian-dylib running on gribozavr4 while building clang at step 6 "test-build-unified-tree-check-clang".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/60/builds/31648

Here is the relevant piece of the build log for the reference

Step 6 (test-build-unified-tree-check-clang) failure: test (failure)
******************** TEST 'Clang :: Driver/autocomplete.c' FAILED ********************
Exit Code: 1

Command Output (stdout):
--



-###	Print (but do not run) the commands to run for this compilation
--amdgpu-arch-tool=	Tool used for detecting AMD GPU arch in the system.
--analyze	Run the static analyzer
--analyzer-output	Static analyzer report output format (html|plist|plist-multi-file|plist-html|sarif|sarif-html|text).
--ansi	
--config-system-dir=	System directory for configuration files
--config-user-dir=	User directory for configuration files
--config=	Specify configuration file
--coverage	
--cuda-compile-host-device	Compile CUDA code for both host and device (default). Has no effect on non-CUDA compilations.
--cuda-device-only	Compile CUDA code for device only
--cuda-feature=	Manually specify the CUDA feature to use
--cuda-gpu-arch=	
--cuda-host-only	Compile CUDA code for host only. Has no effect on non-CUDA compilations.
--cuda-include-ptx=	Include PTX for the following GPU architecture (e.g. sm_35) or 'all'. May be specified more than once.
--cuda-noopt-device-debug	Enable device-side debug info generation. Disables ptxas optimizations.
--cuda-path-ignore-env	Ignore environment variables to detect CUDA installation
--cuda-path=	CUDA installation path
--driver-mode=	Set the driver mode to either 'gcc', 'g++', 'cpp', 'cl' or 'flang'
--dxv-path=	DXIL validator installation path
--embed-dir=	Add directory to embed search path
--emit-extension-symbol-graphs	Generate additional symbol graphs for extended modules.
--emit-static-lib	Enable linker job to emit a static library.
--end-no-unused-arguments	Start emitting warnings for unused driver arguments
--extract-api-ignores=	Comma separated list of files containing a new line separated list of API symbols to ignore when extracting API information.
--gcc-install-dir=	Use GCC installation in the specified directory. The directory ends with path components like 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Note: executables (e.g. ld) used by the compiler are not overridden by the selected GCC installation
--gcc-toolchain=	Specify a directory where Clang can find 'include' and 'lib{,32,64}/gcc{,-cross}/$triple/$version'. Clang will use the GCC installation with the largest version
--gcc-triple=	Search for the GCC installation with the specified triple.
--gpu-bundle-output	Bundle output files of HIP device compilation
--gpu-instrument-lib=	Instrument device library for HIP, which is a LLVM bitcode containing __cyg_profile_func_enter and __cyg_profile_func_exit
--gpu-max-threads-per-block=	Default max threads per block for kernel launch bounds for HIP
--gpu-use-aux-triple-only	Prepare '-aux-triple' only without populating '-aux-target-cpu' and '-aux-target-feature'.
--help	Display available options
--help-hidden	Display help for hidden options
--hip-device-lib-path=	
--hip-device-lib=	HIP device library
--hip-link	Link clang-offload-bundler bundles for HIP
--hip-path=	HIP runtime installation path, used for finding HIP version and adding HIP include path.
--hip-version=	HIP version in the format of major.minor.patch
--hipspv-pass-plugin=	path to a pass plugin for HIP to SPIR-V passes.
--hipstdpar	Enable HIP acceleration for standard parallel algorithms
--hipstdpar-interpose-alloc	Replace all memory allocation / deallocation calls with hipManagedMalloc / hipFree equivalents
...

mikaelholmen · 2025-06-30T12:47:04Z

Hello @ashwinbanwari

With this patch I get

Unexpectedly Passed Tests (5):
  llvm-libc++-shared.cfg.in :: libcxx/selftest/modules/std-and-std.compat-module.sh.cpp
  llvm-libc++-shared.cfg.in :: libcxx/selftest/modules/std-module.sh.cpp
  llvm-libc++-shared.cfg.in :: libcxx/selftest/modules/std.compat-module.sh.cpp
  llvm-libc++-shared.cfg.in :: std/modules/std.compat.pass.cpp
  llvm-libc++-shared.cfg.in :: std/modules/std.pass.cpp

any idea what's happening?

qinkunbao · 2025-06-30T14:10:06Z

Hi, can you take a look at the buildbot failure?

https://lab.llvm.org/buildbot/#/builders/55/builds/13509

ChuanqiXu9 · 2025-06-30T15:16:34Z

Didn't know it. I'll revert this.

@ashwinbanwari it looks like you need to remove the diagnostics with extern "C++" main and apply it with libc++ and land this finally.

This reverts commit 473769e. It breaks test in libc++ See #146247

…46247)" This reverts commit 473769e. It breaks test in libc++ See llvm/llvm-project#146247

Close llvm#146229 As the issue said, main shouldn't be in any modules. new diagnostic output: ``` /my/code/directory/main.cpp:3:1: warning: 'main' should not be attached to a named module; consider adding C++ language linkage [-Wmain] 3 | int main() { | ^ | extern "C++" 1 warning generated. ```

This reverts commit 473769e. It breaks test in libc++ See llvm#146247

Close llvm#146229 As the issue said, main shouldn't be in any modules. new diagnostic output: ``` /my/code/directory/main.cpp:3:1: warning: 'main' should not be attached to a named module; consider adding C++ language linkage [-Wmain] 3 | int main() { | ^ | extern "C++" 1 warning generated. ```

This reverts commit 473769e. It breaks test in libc++ See llvm#146247

This reverts commit 8a5b97a.

Revival of #146247 which got reverted for broken test. Now that #146461 is merged to allow `extern "C++"` for main, we can merge this change.

Revival of llvm/llvm-project#146247 which got reverted for broken test. Now that llvm/llvm-project#146461 is merged to allow `extern "C++"` for main, we can merge this change.

kish1n added 2 commits June 28, 2025 16:19

add err_main_in_named_module

f2ed0c7

git clang-format HEAD~1

b721f8f

llvmbot added clang Clang issues not falling into any other category clang:frontend Language frontend issues, e.g. anything involving "Sema" labels Jun 28, 2025

kish1n changed the title ~~[clang] [modules] add err_main_in_named_module~~ [clang] [modules] Add err_main_in_named_module Jun 28, 2025

don't need FixItHint() ?

6130b53

kish1n and others added 2 commits June 29, 2025 02:01

add release notes and unit test

1f2a548

Merge branch 'main' into ErrMainInNamedModule

b13998c

kish1n added 2 commits June 30, 2025 00:12

Merge branch 'main' into ErrMainInNamedModule

f1ee8b8

change error to warning

1b83608

ChuanqiXu9 approved these changes Jun 30, 2025

View reviewed changes

ChuanqiXu9 reviewed Jun 30, 2025

View reviewed changes

kish1n added 4 commits June 30, 2025 01:03

put warning in diagnostic group -Wmain

96395ec

git clang format

790ecdc

Suggest wrap into language linkage

b6b1b71

add git clang-format

3df1e16

kish1n requested a review from ChuanqiXu9 June 30, 2025 08:25

ChuanqiXu9 reviewed Jun 30, 2025

View reviewed changes

change group to -Wmain-attached-to-named-module

088e4a8

ChuanqiXu9 approved these changes Jun 30, 2025

View reviewed changes

ChuanqiXu9 merged commit 473769e into llvm:main Jun 30, 2025
3 checks passed

kish1n mentioned this pull request Jun 30, 2025

[clang] Fix broken autocomplete test #146326

Closed

ChuanqiXu9 added a commit that referenced this pull request Jun 30, 2025

Revert "[clang] [modules] Add err_main_in_named_module (#146247)"

8a5b97a

This reverts commit 473769e. It breaks test in libc++ See #146247

llvm-sync bot pushed a commit to arm/arm-toolchain that referenced this pull request Jun 30, 2025

Automerge: Revert "[clang] [modules] Add err_main_in_named_module (#1…

1b2dc1b

…46247)" This reverts commit 473769e. It breaks test in libc++ See llvm/llvm-project#146247

rlavaee pushed a commit to rlavaee/llvm-project that referenced this pull request Jul 1, 2025

Revert "[clang] [modules] Add err_main_in_named_module (llvm#146247)"

3c1885a

This reverts commit 473769e. It breaks test in libc++ See llvm#146247

rlavaee pushed a commit to rlavaee/llvm-project that referenced this pull request Jul 1, 2025

Revert "[clang] [modules] Add err_main_in_named_module (llvm#146247)"

9884140

This reverts commit 473769e. It breaks test in libc++ See llvm#146247

kish1n added a commit to kish1n/llvm-project that referenced this pull request Jul 2, 2025

Reapply "[clang] [modules] Add err_main_in_named_module (llvm#146247)"

76bd927

This reverts commit 8a5b97a.

kish1n mentioned this pull request Jul 2, 2025

[clang] [modules] Add err_main_in_named_module #146635

Merged

dominik-steenken mentioned this pull request Jul 2, 2025

[DAG] Add generic expansion for ISD::FCANONICALIZE nodes #142105

Open

ChuanqiXu9 pushed a commit that referenced this pull request Jul 3, 2025

[clang] [modules] Add err_main_in_named_module (#146635)

cc801b6

Revival of #146247 which got reverted for broken test. Now that #146461 is merged to allow `extern "C++"` for main, we can merge this change.

[clang] [modules] Add err_main_in_named_module #146247

[clang] [modules] Add err_main_in_named_module #146247

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