[libunwind] r341404 - [CMake] Don't use -rtlib=compiler-rt with -nodefaultlibs.

[Charles Davis via cfe-commits]

Author: cdavis
Date: Tue Sep  4 13:57:50 2018
New Revision: 341404

URL: http://llvm.org/viewvc/llvm-project?rev=341404&view=rev
Log:
[CMake] Don't use -rtlib=compiler-rt with -nodefaultlibs.

Summary:
This switch only has an effect at link time. It changes the default
compiler support library to `compiler-rt`. With `-nodefaultlibs`, this
library won't get linked anyway; Clang actually warns about that.

Reviewers: mstorsjo, rnk

Subscribers: dberris, mgorny, christof, cfe-commits

Differential Revision: https://reviews.llvm.org/D51645

Modified:
    libunwind/trunk/CMakeLists.txt
    libunwind/trunk/cmake/config-ix.cmake

Modified: libunwind/trunk/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/libunwind/trunk/CMakeLists.txt?rev=341404&r1=341403&r2=341404&view=diff
==============================================================================
--- libunwind/trunk/CMakeLists.txt (original)
+++ libunwind/trunk/CMakeLists.txt Tue Sep  4 13:57:50 2018
@@ -234,7 +234,7 @@ endif()
 # Configure compiler.
 include(config-ix)
 
-if (LIBUNWIND_USE_COMPILER_RT)
+if (LIBUNWIND_USE_COMPILER_RT AND NOT LIBUNWIND_HAS_NODEFAULTLIBS_FLAG)
   list(APPEND LIBUNWIND_LINK_FLAGS "-rtlib=compiler-rt")
 endif()
 

Modified: libunwind/trunk/cmake/config-ix.cmake
URL: http://llvm.org/viewvc/llvm-project/libunwind/trunk/cmake/config-ix.cmake?rev=341404&r1=341403&r2=341404&view=diff
==============================================================================
--- libunwind/trunk/cmake/config-ix.cmake (original)
+++ libunwind/trunk/cmake/config-ix.cmake Tue Sep  4 13:57:50 2018
@@ -23,7 +23,6 @@ if (LIBUNWIND_HAS_NODEFAULTLIBS_FLAG)
     list(APPEND CMAKE_REQUIRED_LIBRARIES c)
   endif ()
   if (LIBUNWIND_USE_COMPILER_RT)
-    list(APPEND CMAKE_REQUIRED_FLAGS -rtlib=compiler-rt)
     find_compiler_rt_library(builtins LIBUNWIND_BUILTINS_LIBRARY)
     list(APPEND CMAKE_REQUIRED_LIBRARIES "${LIBUNWIND_BUILTINS_LIBRARY}")
   elseif (LIBUNWIND_HAS_GCC_S_LIB)