[compiler-rt] 16de508 - honor Python2_EXECUTABLE and Python3_EXECUTABLE when they are passed to cmake

[Michael Kruse via llvm-commits]

Author: Robert Underwood
Date: 2020-11-17T17:49:14-06:00
New Revision: 16de50895e96adbe261a5ce2498366bda7b3fccd

URL: https://github.com/llvm/llvm-project/commit/16de50895e96adbe261a5ce2498366bda7b3fccd
DIFF: https://github.com/llvm/llvm-project/commit/16de50895e96adbe261a5ce2498366bda7b3fccd.diff

LOG: honor Python2_EXECUTABLE and Python3_EXECUTABLE when they are passed to cmake

CMake's find_package(Python3) and find_package(Python2) packages have a PYTHON_EXECUTABLE, Python2_EXECUTABLE, and Python3_EXECUTABLE cmake variables which control which version of python is built against.  As far as I can tell, the rest of LLVM honors these variables. This can cause the build process to fail when  if the automatically selected version of Python can't run due to modifications of LD_LIBRARY_PATH when using spack.  The corresponding Spack issue is https://github.com/spack/spack/issues/19908.  The corresponding LLVM issue is 48180

I believe an appropriate fix is to add the variables to the list of PASSTHROUGH_VARIABLES in cmake/Modules/AddCompilerRT.cmake, and this fixed compilation errors for me.

This bug affects distributions like Gentoo and package managers like Spack which allow for combinatorial versioning.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D91536

Added: 
    

Modified: 
    compiler-rt/cmake/Modules/AddCompilerRT.cmake

Removed: 
    


################################################################################
diff  --git a/compiler-rt/cmake/Modules/AddCompilerRT.cmake b/compiler-rt/cmake/Modules/AddCompilerRT.cmake
index bd1499b4b4d8..0b8db6a868a1 100644
--- a/compiler-rt/cmake/Modules/AddCompilerRT.cmake
+++ b/compiler-rt/cmake/Modules/AddCompilerRT.cmake
@@ -583,6 +583,9 @@ macro(add_custom_libcxx name prefix)
     CMAKE_OBJDUMP
     CMAKE_STRIP
     CMAKE_SYSROOT
+    PYTHON_EXECUTABLE
+    Python3_EXECUTABLE
+    Python2_EXECUTABLE
     CMAKE_SYSTEM_NAME)
   foreach(variable ${PASSTHROUGH_VARIABLES})
     get_property(is_value_set CACHE ${variable} PROPERTY VALUE SET)