3 files changed, 29 insertions, 0 deletions
diff --git a/lib/Driver/ToolChain.cpp b/lib/Driver/ToolChain.cpp
index 9453848ec0..83c918ea64 100644
--- a/lib/Driver/ToolChain.cpp
+++ b/lib/Driver/ToolChain.cpp
@@ -216,6 +216,22 @@ void ToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
   // Each toolchain should provide the appropriate include flags.
 }
 
+ToolChain::RuntimeLibType ToolChain::GetRuntimeLibType(
+  const ArgList &Args) const
+{
+  if (Arg *A = Args.getLastArg(options::OPT_rtlib_EQ)) {
+    StringRef Value = A->getValue(Args);
+    if (Value == "compiler-rt")
+      return ToolChain::RLT_CompilerRT;
+    if (Value == "libgcc")
+      return ToolChain::RLT_Libgcc;
+    getDriver().Diag(diag::err_drv_invalid_rtlib_name)
+      << A->getAsString(Args);
+  }
+
+  return GetDefaultRuntimeLibType();
+}
+
 ToolChain::CXXStdlibType ToolChain::GetCXXStdlibType(const ArgList &Args) const{
   if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) {
     StringRef Value = A->getValue(Args);
diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index fa4cf41889..29559a6ae2 100644
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -440,6 +440,16 @@ void DarwinClang::AddLinkRuntimeLib(const ArgList &Args,
 
 void DarwinClang::AddLinkRuntimeLibArgs(const ArgList &Args,
                                         ArgStringList &CmdArgs) const {
+  // Darwin only supports the compiler-rt based runtime libraries.
+  switch (GetRuntimeLibType(Args)) {
+  case ToolChain::RLT_CompilerRT:
+    break;
+  default:
+    getDriver().Diag(diag::err_drv_unsupported_rtlib_for_platform)
+      << Args.getLastArg(options::OPT_rtlib_EQ)->getValue(Args) << "darwin";
+    return;
+  }
+
   // Darwin doesn't support real static executables, don't link any runtime
   // libraries with -static.
   if (Args.hasArg(options::OPT_static))
diff --git a/lib/Driver/ToolChains.h b/lib/Driver/ToolChains.h
index d150a97693..f3a26e6e11 100644
--- a/lib/Driver/ToolChains.h
+++ b/lib/Driver/ToolChains.h
@@ -347,6 +347,9 @@ public:
       (!isMacosxVersionLT(10, 6) ||
          (!isMacosxVersionLT(10, 5) && !KernelOrKext));
   }
+  virtual RuntimeLibType GetDefaultRuntimeLibType() const {
+    return ToolChain::RLT_CompilerRT;
+  }
   virtual const char *GetDefaultRelocationModel() const;
   virtual const char *GetForcedPicModel() const;