-fcatch-undefined-behavior: emit calls to the runtime library whenever one of the checks fails.

llvm-svn: 165536

1 files changed, 18 insertions, 0 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 468a362b3c4..790b9f0299f 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -1466,6 +1466,23 @@ static void addTsanRTLinux(const ToolChain &TC, const ArgList &Args,
   }
 }
 
+/// If UndefinedBehaviorSanitizer is enabled, add appropriate linker flags
+/// (Linux).
+static void addUbsanRTLinux(const ToolChain &TC, const ArgList &Args,
+                            ArgStringList &CmdArgs) {
+  if (!Args.hasArg(options::OPT_fcatch_undefined_behavior))
+    return;
+  if (!Args.hasArg(options::OPT_shared)) {
+    // LibUbsan is "libclang_rt.ubsan-<ArchName>.a" in the Linux library
+    // resource directory.
+    SmallString<128> LibUbsan(TC.getDriver().ResourceDir);
+    llvm::sys::path::append(LibUbsan, "lib", "linux",
+                            (Twine("libclang_rt.ubsan-") +
+                             TC.getArchName() + ".a"));
+    CmdArgs.push_back(Args.MakeArgString(LibUbsan));
+  }
+}
+
 static bool shouldUseFramePointer(const ArgList &Args,
                                   const llvm::Triple &Triple) {
   if (Arg *A = Args.getLastArg(options::OPT_fno_omit_frame_pointer,
@@ -5911,6 +5928,7 @@ void linuxtools::Link::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   addProfileRT(getToolChain(), Args, CmdArgs, getToolChain().getTriple());
+  addUbsanRTLinux(getToolChain(), Args, CmdArgs);
 
   C.addCommand(new Command(JA, *this, ToolChain.Linker.c_str(), CmdArgs));
 }