[PATCH] CFE Knob for: Add a thread-model knob for lowering atomics on baremetal & single threaded systems

[hfinkel at anl.gov]

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Comment at: lib/Frontend/CompilerInvocation.cpp:440
@@ -439,2 +439,3 @@
   Opts.RelocationModel = Args.getLastArgValue(OPT_mrelocation_model, "pic");
+  Opts.ThreadModel = Args.getLastArgValue(OPT_mthread_model, "POSIX");
   Opts.TrapFuncName = Args.getLastArgValue(OPT_ftrap_function_EQ);
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You need to validate the string here (just asserting later is not acceptable). There are plenty of calls to Diags.Report in this file, you'll need to add another.

Then you'll need a regression test for this.

http://reviews.llvm.org/D4985