[Openmp-commits] [openmp] 432a7e2 - [libomp] Add -Wl, --undefined-version workaround

[Fangrui Song via Openmp-commits]

Author: Fangrui Song
Date: 2022-11-07T22:15:28Z
New Revision: 432a7e284440c719637fe34b972c96c9af0e01f1

URL: https://github.com/llvm/llvm-project/commit/432a7e284440c719637fe34b972c96c9af0e01f1
DIFF: https://github.com/llvm/llvm-project/commit/432a7e284440c719637fe34b972c96c9af0e01f1.diff

LOG: [libomp] Add -Wl,--undefined-version workaround

Issue #58858: when linking libomp.so, exports_so.txt has non-existent/undefined
symbols which cause errors to ld --no-undefined-version. Use
-Wl,--undefined-version if available (gold, ld.lld, future GNU ld 2.40).

Added: 
    

Modified: 
    openmp/runtime/cmake/LibompHandleFlags.cmake
    openmp/runtime/cmake/config-ix.cmake

Removed: 
    


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diff  --git a/openmp/runtime/cmake/LibompHandleFlags.cmake b/openmp/runtime/cmake/LibompHandleFlags.cmake
index aee9038520b8a..33847b5545fbc 100644
--- a/openmp/runtime/cmake/LibompHandleFlags.cmake
+++ b/openmp/runtime/cmake/LibompHandleFlags.cmake
@@ -100,6 +100,7 @@ function(libomp_get_ldflags ldflags)
   libomp_append(ldflags_local -Wl,--warn-shared-textrel LIBOMP_HAVE_WARN_SHARED_TEXTREL_FLAG)
   libomp_append(ldflags_local -Wl,--as-needed LIBOMP_HAVE_AS_NEEDED_FLAG)
   libomp_append(ldflags_local "-Wl,--version-script=${LIBOMP_SRC_DIR}/exports_so.txt" LIBOMP_HAVE_VERSION_SCRIPT_FLAG)
+  libomp_append(ldflags_local "-Wl,--undefined-version" LIBOMP_HAVE_UNDEFINED_VERSION_FLAG)  # FIXME issue #58858
   libomp_append(ldflags_local -static-libgcc LIBOMP_HAVE_STATIC_LIBGCC_FLAG)
   libomp_append(ldflags_local -Wl,-z,noexecstack LIBOMP_HAVE_Z_NOEXECSTACK_FLAG)
   libomp_append(ldflags_local -no-intel-extensions LIBOMP_HAVE_NO_INTEL_EXTENSIONS_FLAG)

diff  --git a/openmp/runtime/cmake/config-ix.cmake b/openmp/runtime/cmake/config-ix.cmake
index a57cbf9d2ef59..ac6c81670211b 100644
--- a/openmp/runtime/cmake/config-ix.cmake
+++ b/openmp/runtime/cmake/config-ix.cmake
@@ -133,6 +133,7 @@ elseif(NOT APPLE)
   libomp_check_linker_flag(-Wl,--warn-shared-textrel LIBOMP_HAVE_WARN_SHARED_TEXTREL_FLAG)
   libomp_check_linker_flag(-Wl,--as-needed LIBOMP_HAVE_AS_NEEDED_FLAG)
   libomp_check_linker_flag("-Wl,--version-script=${LIBOMP_SRC_DIR}/exports_so.txt" LIBOMP_HAVE_VERSION_SCRIPT_FLAG)
+  libomp_check_linker_flag("-Wl,--undefined-version" LIBOMP_HAVE_UNDEFINED_VERSION_FLAG)  # FIXME issue #58858
   libomp_check_linker_flag(-static-libgcc LIBOMP_HAVE_STATIC_LIBGCC_FLAG)
   libomp_check_linker_flag(-Wl,-z,noexecstack LIBOMP_HAVE_Z_NOEXECSTACK_FLAG)
 endif()