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

[Tim Northover]

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Comment at: lib/CodeGen/BackendUtil.cpp:431
@@ +430,3 @@
+      .Case("posix", llvm::ThreadModel::POSIX)
+      .Case("single", llvm::ThreadModel::Single);
+
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rengolin wrote:
> Shouldn't this have a .Default()? If so, which value?
And is "posix" really the best term for the C++11 model? Windows has just as much history of threading, and it was all rather a bodge before the C++11 description came around.

http://reviews.llvm.org/D4985