From: Michał Górny <mgorny@gentoo.org>
Date: Sat, 1 Oct 2016 18:58:18 +0000 (+0200)
Subject: sys-libs/compiler-rt: Support bootstrapping with runtime-less clang
X-Git-Url: http://git.tremily.us/gitweb.cgi?a=commitdiff_plain;h=93a7dfc1e15d39ae382e56d6da1e775e08efbdd3;p=gentoo.git

sys-libs/compiler-rt: Support bootstrapping with runtime-less clang
---

diff --git a/sys-libs/compiler-rt/compiler-rt-9999.ebuild b/sys-libs/compiler-rt/compiler-rt-9999.ebuild
index 751fac90d8b0..1f8d17441573 100644
--- a/sys-libs/compiler-rt/compiler-rt-9999.ebuild
+++ b/sys-libs/compiler-rt/compiler-rt-9999.ebuild
@@ -9,7 +9,7 @@ CMAKE_MIN_VERSION=3.4.3
 PYTHON_COMPAT=( python2_7 )
 
 # TODO: fix unnecessary dep on Python upstream
-inherit cmake-utils flag-o-matic git-r3 python-any-r1
+inherit cmake-utils flag-o-matic git-r3 python-any-r1 toolchain-funcs
 
 DESCRIPTION="Compiler runtime library for clang (built-in part)"
 HOMEPAGE="http://llvm.org/"
@@ -28,10 +28,23 @@ DEPEND="${RDEPEND}
 	~sys-devel/llvm-${PV}
 	${PYTHON_DEPS}"
 
+test_compiler() {
+	$(tc-getCC) ${CFLAGS} ${LDFLAGS} "${@}" -o /dev/null -x c - \
+		<<<'int main() { return 0; }' &>/dev/null
+}
+
 src_configure() {
 	# pre-set since we need to pass it to cmake
 	BUILD_DIR=${WORKDIR}/${P}_build
 
+	if ! test_compiler; then
+		local extra_flags=( -nodefaultlibs -lc )
+		if test_compiler "${extra_flags[@]}"; then
+			local -x LDFLAGS="${LDFLAGS} ${extra_flags[*]}"
+			ewarn "${CC} seems to lack runtime, trying with ${extra_flags[*]}"
+		fi
+	fi
+
 	local clang_version=4.0.0
 	local libdir=$(get_libdir)
 	local mycmakeargs=(