Teach the LLVM CMake build how to explicitly use libc++abi when using

libc++. This lets me almost self-host on Linux with libc++ and libc++abi
very simply.

Currently, MCJIT and OrcJIT are failing due to uncaught exceptions, and
the Go binding tests are failing to build due to not linking in the
correct C++ standard library.

llvm-svn: 231560

1 files changed, 16 insertions, 10 deletions

diff --git a/llvm/cmake/modules/HandleLLVMStdlib.cmake b/llvm/cmake/modules/HandleLLVMStdlib.cmake
index 47bb6cddc8e..66ad078fb66 100644
--- a/llvm/cmake/modules/HandleLLVMStdlib.cmake
+++ b/llvm/cmake/modules/HandleLLVMStdlib.cmake
@@ -12,22 +12,28 @@ if(NOT DEFINED LLVM_STDLIB_HANDLED)
     set(LLVM_COMPILER_IS_GCC_COMPATIBLE ON)
   endif()
 
-  function(append_if condition value)
-    if(${condition})
-      foreach(variable ${ARGN})
-        set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
-      endforeach(variable)
-    endif()
+  function(append value)
+    foreach(variable ${ARGN})
+      set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
+    endforeach(variable)
   endfunction()
 
   include(CheckCXXCompilerFlag)
   if(LLVM_ENABLE_LIBCXX)
     if(LLVM_COMPILER_IS_GCC_COMPATIBLE)
       check_cxx_compiler_flag("-stdlib=libc++" CXX_SUPPORTS_STDLIB)
-      append_if(CXX_SUPPORTS_STDLIB "-stdlib=libc++" CMAKE_CXX_FLAGS)
-      append_if(CXX_SUPPORTS_STDLIB "-stdlib=libc++" CMAKE_EXE_LINKER_FLAGS)
-      append_if(CXX_SUPPORTS_STDLIB "-stdlib=libc++" CMAKE_SHARED_LINKER_FLAGS)
-      append_if(CXX_SUPPORTS_STDLIB "-stdlib=libc++" CMAKE_MODULE_LINKER_FLAGS)
+      if(CXX_SUPPORTS_STDLIB)
+        append("-stdlib=libc++"
+          CMAKE_CXX_FLAGS CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS
+          CMAKE_MODULE_LINKER_FLAGS)
+        if(LLVM_ENABLE_LIBCXXABI)
+          append("-lc++abi"
+            CMAKE_EXE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS
+            CMAKE_MODULE_LINKER_FLAGS)
+        endif()
+      else()
+        message(WARNING "Can't specify libc++ with '-stdlib='")
+      endif()
     else()
       message(WARNING "Not sure how to specify libc++ for this compiler")
     endif()