Prevent warning spew about -fPIC when using CMake generated Xcode project files.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86427 91177308-0d34-0410-b5e6-96231b3b80d8

CMakeLists.txt

@@ -164,13 +164,19 @@ option(LLVM_ENABLE_PIC "Build Position-Independent Code" ON)
 
 set(ENABLE_PIC 0)
 if( LLVM_ENABLE_PIC )
-  if( SUPPORTS_FPIC_FLAG )
-    message(STATUS "Building with -fPIC")
-    add_llvm_definitions(-fPIC)
-    set(ENABLE_PIC 1)
- else( SUPPORTS_FPIC_FLAG )
-    message(STATUS "Warning: -fPIC not supported.")
-  endif()
+ if( XCODE )
+   # Xcode has -mdynamic-no-pic on by default, which overrides -fPIC. I don't
+   # know how to disable this, so just force ENABLE_PIC off for now.
+   message(STATUS "Warning: -fPIC not supported with Xcode.")
+ else( XCODE )
+   if( SUPPORTS_FPIC_FLAG )
+      message(STATUS "Building with -fPIC")
+      add_llvm_definitions(-fPIC)
+      set(ENABLE_PIC 1)
+   else( SUPPORTS_FPIC_FLAG )
+      message(STATUS "Warning: -fPIC not supported.")
+   endif()
+ endif()
 endif()
 
 set( CMAKE_RUNTIME_OUTPUT_DIRECTORY ${LLVM_TOOLS_BINARY_DIR} )