[PATCH] Make sure globals created by UBSan are not instrumented by ASan.

[Richard Smith]

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Comment at: lib/CodeGen/CGExpr.cpp:2179-2180
@@ +2178,4 @@
+  if (PLoc.isValid()) {
+    auto FilenameGV = CGM.GetAddrOfConstantCString(PLoc.getFilename(), ".src");
+    CGM.disableSanitizerForGlobal(FilenameGV);
+    Filename = FilenameGV;
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I'm concerned about this one: these strings may be shared by other parts of the program, where ASan instrumentation is important. How much does instrumenting these strings cost us?

http://reviews.llvm.org/D4575