[compiler-rt] r271256 - [asan] Fix a deadlock halt_on_error-signals.c when `reporting_thread_tid_` is 0

[Kuba Brecka via llvm-commits]

Author: kuba.brecka
Date: Tue May 31 03:47:18 2016
New Revision: 271256

URL: http://llvm.org/viewvc/llvm-project?rev=271256&view=rev
Log:
[asan] Fix a deadlock halt_on_error-signals.c when `reporting_thread_tid_` is 0

A signal can be delivered after TryLock but before StartReporting in ScopedInErrorReport, causing a deadlock.  Fixing this by statically initializing reporting_thread_tid_ to kInvalidTid.

Differential Revision: http://reviews.llvm.org/D20524


Modified:
    compiler-rt/trunk/lib/asan/asan_report.cc

Modified: compiler-rt/trunk/lib/asan/asan_report.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_report.cc?rev=271256&r1=271255&r2=271256&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_report.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_report.cc Tue May 31 03:47:18 2016
@@ -736,7 +736,7 @@ class ScopedInErrorReport {
 };
 
 StaticSpinMutex ScopedInErrorReport::lock_;
-u32 ScopedInErrorReport::reporting_thread_tid_;
+u32 ScopedInErrorReport::reporting_thread_tid_ = kInvalidTid;
 
 void ReportStackOverflow(const SignalContext &sig) {
   ScopedInErrorReport in_report(/*report*/ nullptr, /*fatal*/ true);