From ae3b01cf8af01ce58a18d380548d17d0f056c0a5 Mon Sep 17 00:00:00 2001
From: Shantonu Sen <ssen@apple.com>
Date: Wed, 23 Sep 2009 16:05:25 +0000
Subject: [PATCH] If the compiler does not support GCC-compatible atomic
 operations, skip building the blocks runtime

llvm-svn: 82627
---
 compiler-rt/CMakeLists.txt | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/compiler-rt/CMakeLists.txt b/compiler-rt/CMakeLists.txt
index 064fde0afe38..9c458477d7ca 100644
--- a/compiler-rt/CMakeLists.txt
+++ b/compiler-rt/CMakeLists.txt
@@ -34,9 +34,19 @@ SET( Configurations
  Debug Release Profile
  )
 
-# BlocksRuntime - some random cruft that got thrown in at the last minute, ignoring for now.
-ADD_SUBDIRECTORY( BlocksRuntime )
+# Only build Blocks Runtime if the compiler has enough support
+IF( WIN32 OR MSVC OR HAVE_OSATOMIC_COMPARE_AND_SWAP_INT OR HAVE_SYNC_BOOL_COMPARE_AND_SWAP_INT )
+  SET(BUILD_BLOCKS_RUNTIME TRUE)
+ELSE( WIN32 OR MSVC OR HAVE_OSATOMIC_COMPARE_AND_SWAP_INT OR HAVE_SYNC_BOOL_COMPARE_AND_SWAP_INT )
+  SET(BUILD_BLOCKS_RUNTIME FALSE)
+ENDIF( WIN32 OR MSVC OR HAVE_OSATOMIC_COMPARE_AND_SWAP_INT OR HAVE_SYNC_BOOL_COMPARE_AND_SWAP_INT )
 
+IF( BUILD_BLOCKS_RUNTIME )
+  ADD_SUBDIRECTORY( BlocksRuntime )
+ELSE( BUILD_BLOCKS_RUNTIME )
+  MESSAGE(STATUS "No suitable atomic operation routines detected, skipping Blocks Runtime")
+ENDIF( BUILD_BLOCKS_RUNTIME )
+ 
 ADD_SUBDIRECTORY( lib )
 
 # Tests are being ignored for until the very basics are working.