From b98a74738a027ba7d5f81ef49a154b7c90b80995 Mon Sep 17 00:00:00 2001
From: David Carlos Manuelda <StormByte@gmail.com>
Date: Fri, 26 Oct 2018 19:39:17 +0000
Subject: [PATCH] Fix compiler-rt detection and linkage as of bug #592326

---
 .../libcxx-7.0.0-fix-compiler-rt-detection.patch      | 11 +++++++++++
 sys-libs/libcxx/libcxx-7.0.0.ebuild                   | 11 +++++++----
 2 files changed, 18 insertions(+), 4 deletions(-)
 create mode 100644 sys-libs/libcxx/files/libcxx-7.0.0-fix-compiler-rt-detection.patch

diff --git a/sys-libs/libcxx/files/libcxx-7.0.0-fix-compiler-rt-detection.patch b/sys-libs/libcxx/files/libcxx-7.0.0-fix-compiler-rt-detection.patch
new file mode 100644
index 000000000..0cf9678c7
--- /dev/null
+++ b/sys-libs/libcxx/files/libcxx-7.0.0-fix-compiler-rt-detection.patch
@@ -0,0 +1,11 @@
+--- a/cmake/Modules/HandleCompilerRT.cmake	2018-10-26 19:17:14.955186526 -0000
++++ b/cmake/Modules/HandleCompilerRT.cmake	2018-10-26 19:17:48.613187357 -0000
+@@ -3,7 +3,7 @@
+     message(FATAL_ERROR "LIBCXX_COMPILE_FLAGS must be defined when using this function")
+   endif()
+   set(dest "" PARENT_SCOPE)
+-  set(CLANG_COMMAND ${CMAKE_CXX_COMPILER} ${LIBCXX_COMPILE_FLAGS}
++  set(CLANG_COMMAND ${CMAKE_CXX_COMPILER} -m${LIBCXX_LIBDIR_SUFFIX} ${LIBCXX_COMPILE_FLAGS}
+       "--rtlib=compiler-rt" "--print-libgcc-file-name")
+   if (CMAKE_CXX_COMPILER_ID MATCHES Clang AND CMAKE_CXX_COMPILER_TARGET)
+     list(APPEND CLANG_COMMAND "--target=${CMAKE_CXX_COMPILER_TARGET}")
diff --git a/sys-libs/libcxx/libcxx-7.0.0.ebuild b/sys-libs/libcxx/libcxx-7.0.0.ebuild
index 790f5dc12..099088fa4 100644
--- a/sys-libs/libcxx/libcxx-7.0.0.ebuild
+++ b/sys-libs/libcxx/libcxx-7.0.0.ebuild
@@ -50,6 +50,10 @@ PATCHES=(
 	# Fix installing when using libsupc++ backend.
 	# https://bugs.gentoo.org/667174
 	"${FILESDIR}/${PN}-7.0.0-libsupcxx-install.patch"
+
+	# Fix compiler-rt detection and linking while linking against libunwind
+	# https://bugs.gentoo.org/592326
+	"${FILESDIR}/${PN}-${PV}-fix-compiler-rt-detection.patch"
 )
 
 # least intrusive of all
@@ -104,7 +108,7 @@ src_configure() {
 multilib_src_configure() {
 	# we want -lgcc_s for unwinder, and for compiler runtime when using
 	# gcc, clang with gcc runtime (or any unknown compiler)
-	local extra_libs=() want_gcc_s=ON
+	local extra_libs=() use_compiler_rt=OFF
 	if use libunwind; then
 		# work-around missing -lunwind upstream
 		extra_libs+=( -lunwind )
@@ -114,8 +118,7 @@ multilib_src_configure() {
 			local compiler_rt=$($(tc-getCC) ${CFLAGS} ${CPPFLAGS} \
 			   ${LDFLAGS} -print-libgcc-file-name)
 			if [[ ${compiler_rt} == *libclang_rt* ]]; then
-				want_gcc_s=OFF
-				extra_libs+=( "${compiler_rt}" )
+				use_compiler_rt=ON
 			fi
 		fi
 	fi
@@ -139,7 +142,7 @@ multilib_src_configure() {
 		# we're using our own mechanism for generating linker scripts
 		-DLIBCXX_ENABLE_ABI_LINKER_SCRIPT=OFF
 		-DLIBCXX_HAS_MUSL_LIBC=$(usex elibc_musl)
-		-DLIBCXX_HAS_GCC_S_LIB=${want_gcc_s}
+		-DLIBCXX_USE_COMPILER_RT=${use_compiler_rt}
 		-DLIBCXX_INCLUDE_TESTS=$(usex test)
 		-DCMAKE_SHARED_LINKER_FLAGS="${extra_libs[*]} ${LDFLAGS}"
 	)
-- 
2.19.1