[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
git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@341404 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index d73c0dd..bab9e08 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -234,7 +234,7 @@
# 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()
diff --git a/cmake/config-ix.cmake b/cmake/config-ix.cmake
index 2d4da64..f4f9ee8 100644
--- a/cmake/config-ix.cmake
+++ b/cmake/config-ix.cmake
@@ -23,7 +23,6 @@
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)
