[PATCH] [ASan] Make stack-buffer-overflow reports more robust

[Alexey Samsonov]

Testing this is hard. I've tested this change on a large program with racy use-after-return, and failed to reproduce this in a small test case.

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Comment at: lib/asan/asan_report.cc:458
@@ -456,1 +457,3 @@
   // Report all objects in this frame.
+  const uptr kBufSize = 4095;
+  char buf[kBufSize];
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kcc wrote:
> Isn't this buffer too large? (we may get stack overflow while reporting)
Yeah, we may get rid of this buffer completely. I'll address this in a separate change.

http://reviews.llvm.org/D5554