Merging r312748:

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r312748 | jroelofs | 2017-09-07 15:01:25 -0700 (Thu, 07 Sep 2017) | 10 lines

Fix validation of the -mthread-model flag in the Clang driver

The ToolChain class validates the -mthread-model flag in the constructor which
doesn't work correctly since the thread model methods are virtual methods. The
check is moved into Clang::ConstructJob() when constructing the internal
command line.

https://reviews.llvm.org/D37496

Patch by: Ian Tessier!
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git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_50@318346 91177308-0d34-0410-b5e6-96231b3b80d8

Author: tstellar

lib/Driver/ToolChain.cpp

@@ -74,11 +74,6 @@ ToolChain::ToolChain(const Driver &D, const llvm::Triple &T,
     : D(D), Triple(T), Args(Args), CachedRTTIArg(GetRTTIArgument(Args)),
       CachedRTTIMode(CalculateRTTIMode(Args, Triple, CachedRTTIArg)),
       EffectiveTriple() {
-  if (Arg *A = Args.getLastArg(options::OPT_mthread_model))
-    if (!isThreadModelSupported(A->getValue()))
-      D.Diag(diag::err_drv_invalid_thread_model_for_target)
-          << A->getValue() << A->getAsString(Args);
-
   std::string CandidateLibPath = getArchSpecificLibPath();
   if (getVFS().exists(CandidateLibPath))
     getFilePaths().push_back(CandidateLibPath);

lib/Driver/ToolChains/Clang.cpp

@@ -2227,8 +2227,12 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   }
 
   CmdArgs.push_back("-mthread-model");
-  if (Arg *A = Args.getLastArg(options::OPT_mthread_model))
+  if (Arg *A = Args.getLastArg(options::OPT_mthread_model)) {
+    if (!getToolChain().isThreadModelSupported(A->getValue()))
+      D.Diag(diag::err_drv_invalid_thread_model_for_target)
+          << A->getValue() << A->getAsString(Args);
     CmdArgs.push_back(A->getValue());
+  }
   else
     CmdArgs.push_back(Args.MakeArgString(getToolChain().getThreadModel()));