CMake: when building shared libraries, use -fPIC for compiling

partially linked objects.

llvm-svn: 59699

llvm/cmake/config-ix.cmake

@@ -52,6 +52,9 @@ check_symbol_exists(mallinfo malloc.h HAVE_MALLINFO)
 check_symbol_exists(pthread_mutex_lock pthread.h HAVE_PTHREAD_MUTEX_LOCK)
 check_symbol_exists(strtoll stdlib.h HAVE_STRTOLL)
 
+include(CheckCXXCompilerFlag)
+check_cxx_compiler_flag("-fPIC" SUPPORTS_FPIC_FLAG)
+
 include(GetTargetTriple)
 get_target_triple(LLVM_HOSTTRIPLE)
 message(STATUS "LLVM_HOSTTRIPLE: ${LLVM_HOSTTRIPLE}")

llvm/cmake/modules/AddPartiallyLinkedObject.cmake

@@ -17,6 +17,9 @@ macro(add_partially_linked_object lib)
     set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/temp_lib)
     set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/temp_lib)
     llvm_process_sources( ALL_FILES ${ARGN} )
+    if( BUILD_SHARED_LIBS AND SUPPORTS_FPIC_FLAG )
+      add_definitions(-fPIC)
+    endif()
     add_library( ${lib} STATIC ${ALL_FILES})
     if( LLVM_COMMON_DEPENDS )
       add_dependencies( ${lib} ${LLVM_COMMON_DEPENDS} )