tsan: fix unitialized read warning under newer gcc (it does not have visibility into asm)


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@186495 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/sanitizer_common/sanitizer_linux.cc b/lib/sanitizer_common/sanitizer_linux.cc
index bd48c67..bbc41f4 100644
--- a/lib/sanitizer_common/sanitizer_linux.cc
+++ b/lib/sanitizer_common/sanitizer_linux.cc
@@ -215,7 +215,7 @@
 }
 
 u64 NanoTime() {
-  kernel_timeval tv;
+  kernel_timeval tv = {};
   internal_syscall(__NR_gettimeofday, &tv, 0);
   return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000;
 }