[llvm] r316956 - [CMake] Fix linker detection in AddLLVM.cmake

[Tim Shen via llvm-commits]

Author: timshen
Date: Mon Oct 30 14:12:14 2017
New Revision: 316956

URL: http://llvm.org/viewvc/llvm-project?rev=316956&view=rev
Log:
[CMake] Fix linker detection in AddLLVM.cmake

Fix linker not being correctly detected when a custom one is specified
through LLVM_USE_LINKER CMake variable.

In particular,

  cmake -DCMAKE_BUILD_TYPE=Release -DLLVM_USE_LINKER=gold ../llvm

resulted into

  Linker detection: GNU ld

instead of

  Linker detection: GNU Gold

due to the construction not accounting for such variable. It led to the general
confusion and prevented setting linker-specific flags inside functions defined
in AddLLVM.cmake.

Thanks Oleksii Vilchanskyi for the patch!

Modified:
    llvm/trunk/cmake/modules/AddLLVM.cmake

Modified: llvm/trunk/cmake/modules/AddLLVM.cmake
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/cmake/modules/AddLLVM.cmake?rev=316956&r1=316955&r2=316956&view=diff
==============================================================================
--- llvm/trunk/cmake/modules/AddLLVM.cmake (original)
+++ llvm/trunk/cmake/modules/AddLLVM.cmake Mon Oct 30 14:12:14 2017
@@ -149,8 +149,13 @@ endfunction(add_llvm_symbol_exports)
 
 if(NOT WIN32 AND NOT APPLE)
   # Detect what linker we have here
+  if( LLVM_USE_LINKER )
+    set(command ${CMAKE_C_COMPILER} -fuse-ld=${LLVM_USE_LINKER} -Wl,--version)
+  else()
+    set(command ${CMAKE_C_COMPILER} -Wl,--version)
+  endif()
   execute_process(
-    COMMAND ${CMAKE_C_COMPILER} -Wl,--version
+    COMMAND ${command}
     OUTPUT_VARIABLE stdout
     ERROR_VARIABLE stderr
     )