[Openmp-commits] [openmp] df9e068 - [OpenMP][CMake] Fix the device runtime build with LLVM_USE_SPLIT_DWARF (#220322)

[via Openmp-commits]

Author: Abid Qadeer
Date: 2026-09-03T16:56:59+01:00
New Revision: df9e06826c294818818358be1267c38a0455679d

URL: https://github.com/llvm/llvm-project/commit/df9e06826c294818818358be1267c38a0455679d
DIFF: https://github.com/llvm/llvm-project/commit/df9e06826c294818818358be1267c38a0455679d.diff

LOG: [OpenMP][CMake] Fix the device runtime build with LLVM_USE_SPLIT_DWARF (#220322)

Building with LLVM_USE_SPLIT_DWARF fails in the GPU runtimes:

  ld.lld: error: -r and --gdb-index may not be used together

HandleLLVMOptions appends -Wl,--gdb-index to CMAKE_EXE_LINKER_FLAGS, and
libompdevice is an add_executable, so it inherits the flag. Its link is
not a real link at all: -flto -r -Wl,--lto-emit-llvm merges the objects
into a single bitcode file, for which a gdb index is meaningless.

Fix is to turn it off for the target.

Co-authored-by: Cursor <cursoragent at cursor.com>

Added: 
    

Modified: 
    openmp/device/CMakeLists.txt

Removed: 
    


################################################################################
diff  --git a/openmp/device/CMakeLists.txt b/openmp/device/CMakeLists.txt
index a41cc58669383..1c486be1ef12a 100644
--- a/openmp/device/CMakeLists.txt
+++ b/openmp/device/CMakeLists.txt
@@ -79,8 +79,13 @@ target_include_directories(libompdevice PRIVATE
 target_compile_options(libompdevice PRIVATE ${compile_options})
 if(NOT "${LLVM_DEFAULT_TARGET_TRIPLE}" MATCHES "^spirv" AND
    NOT "${CMAKE_CXX_COMPILER_TARGET}" MATCHES "^spirv")
+  # LLVM_USE_SPLIT_DWARF puts -Wl,--gdb-index in CMAKE_EXE_LINKER_FLAGS, which
+  # every executable target inherits. A gdb index means nothing for a
+  # relocatable link that emits bitcode, and lld rejects the combination, so
+  # drop it again here.
   target_link_options(libompdevice PRIVATE
-                  "-flto" "-r" "-nostdlib" "-Wl,--lto-emit-llvm")
+                  "-flto" "-r" "-nostdlib" "-Wl,--lto-emit-llvm"
+                  "-Wl,--no-gdb-index")
 else()
   target_link_options(libompdevice PRIVATE
                   "-nostdlib" "-emit-llvm")