[Openmp-commits] [openmp] [OpenMP] [cmake] Don't use -fno-semantic-interposition on Windows (PR #81113)

[via Openmp-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-openmp

Author: Martin Storsjö (mstorsjo)

<details>
<summary>Changes</summary>

This was added in 4b7beab4187ab0766c3d7b272511d5751431a8da. When the flag was added implicitly elsewhere, it was added via llvm/cmake/modules/HandleLLVMOptions.cmake, where it wasn't added on Windows/Cygwin targets.

This avoids one warning per object file in OpenMP.

---
Full diff: https://github.com/llvm/llvm-project/pull/81113.diff


1 Files Affected:

- (modified) openmp/cmake/HandleOpenMPOptions.cmake (+5-1) 


``````````diff
diff --git a/openmp/cmake/HandleOpenMPOptions.cmake b/openmp/cmake/HandleOpenMPOptions.cmake
index 71346201129b68..9387d9b3b0ff75 100644
--- a/openmp/cmake/HandleOpenMPOptions.cmake
+++ b/openmp/cmake/HandleOpenMPOptions.cmake
@@ -46,7 +46,11 @@ append_if(OPENMP_HAVE_WEXTRA_FLAG "-Wno-extra" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
 append_if(OPENMP_HAVE_WPEDANTIC_FLAG "-Wno-pedantic" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
 append_if(OPENMP_HAVE_WMAYBE_UNINITIALIZED_FLAG "-Wno-maybe-uninitialized" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
 
-append_if(OPENMP_HAVE_NO_SEMANTIC_INTERPOSITION "-fno-semantic-interposition" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+if (NOT (WIN32 OR CYGWIN))
+  # This flag is not relevant on Windows; the flag is accepted, but produces warnings
+  # about argument unused during compilation.
+  append_if(OPENMP_HAVE_NO_SEMANTIC_INTERPOSITION "-fno-semantic-interposition" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+endif()
 append_if(OPENMP_HAVE_FUNCTION_SECTIONS "-ffunction-section" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
 append_if(OPENMP_HAVE_DATA_SECTIONS "-fdata-sections" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
 

``````````

</details>


https://github.com/llvm/llvm-project/pull/81113