clang: Add libunwind automatically to link cmdline when using compiler-rt

This makes compile-rt equal to libgcc which has both builtins+unwind as
well

Signed-off-by: Khem Raj <raj.khem@gmail.com>

2 files changed, 24 insertions, 0 deletions

diff --git a/recipes-devtools/clang/clang/0016-clang-Append-libunwind-to-compiler-rt-for-linking.patch b/recipes-devtools/clang/clang/0016-clang-Append-libunwind-to-compiler-rt-for-linking.patch
new file mode 100644
index 0000000..d5c67d1
--- /dev/null
+++ b/recipes-devtools/clang/clang/0016-clang-Append-libunwind-to-compiler-rt-for-linking.patch
@@ -0,0 +1,23 @@
+From 4b5386fe67b03923b7ce25c066e6f6220a32eb44 Mon Sep 17 00:00:00 2001
+From: Khem Raj <raj.khem@gmail.com>
+Date: Fri, 25 Jan 2019 14:39:04 -0800
+Subject: [PATCH] clang: Append libunwind to compiler-rt for linking
+
+Some packages which use libgcc tend to use low level unwind functions
+too, and they are missing in compiler-rt but provided by llvm libunwind
+
+Signed-off-by: Khem Raj <raj.khem@gmail.com>
+---
+ clang/lib/Driver/ToolChains/CommonArgs.cpp | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
++++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
+@@ -1191,6 +1191,7 @@ void tools::AddRunTimeLibs(const ToolCha
+   switch (RLT) {
+   case ToolChain::RLT_CompilerRT:
+     CmdArgs.push_back(TC.getCompilerRTArgString(Args, "builtins"));
++    CmdArgs.push_back(Args.MakeArgString(D.SysRoot + "/usr/lib" "/libunwind.a"));
+     break;
+   case ToolChain::RLT_Libgcc:
+     // Make sure libgcc is not used under MSVC environment by default
diff --git a/recipes-devtools/clang/common.inc b/recipes-devtools/clang/common.inc
index ad1f435..0d9445a 100644
--- a/recipes-devtools/clang/common.inc
+++ b/recipes-devtools/clang/common.inc
@@ -24,6 +24,7 @@ SRC_URI = "\
     file://0013-compiler-rt-support-a-new-embedded-linux-target.patch \
     file://0014-compiler-rt-Simplify-cross-compilation.-Don-t-use-na.patch \
     file://0015-compiler-rt-Disable-tsan-on-OE-glibc.patch \
+    file://0016-clang-Append-libunwind-to-compiler-rt-for-linking.patch \
 "
 
 # Fallback to no-PIE if not set