[libunwind][CMake] Use libc++ headers when available
libunwind depends on C++ library headers. When building libunwind
as part of LLVM and libc++ is available, use its headers.
Differential Revision: https://reviews.llvm.org/D29800
git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@295153 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3ba4b65..ed14e06 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -282,4 +282,24 @@
include_directories(include)
+find_path(
+ LIBUNWIND_LIBCXX_INCLUDES_INTERNAL
+ __libcpp_version
+ PATHS ${LLVM_MAIN_SRC_DIR}/projects/libcxx/include
+ ${LLVM_MAIN_SRC_DIR}/runtimes/libcxx/include
+ NO_DEFAULT_PATH
+)
+if ((NOT LIBUNWIND_STANDALONE_BUILD OR HAVE_LIBCXX) AND
+ IS_DIRECTORY "${LIBUNWIND_LIBCXX_INCLUDES_INTERNAL}")
+ set(LIBUNWIND_CXX_INCLUDE_PATHS_DEFAULT "${LIBUNWIND_LIBCXX_INCLUDES_INTERNAL}")
+endif()
+
+set(LIBUNWIND_CXX_INCLUDE_PATHS "${LIBUNWIND_CXX_INCLUDE_PATHS_DEFAULT}" CACHE PATH
+ "Paths to C++ header directories separated by ';'.")
+
+if (NOT LIBUNWIND_CXX_INCLUDE_PATHS STREQUAL "")
+ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -nostdinc++")
+ include_directories("${LIBUNWIND_CXX_INCLUDE_PATHS}")
+endif()
+
add_subdirectory(src)
