[tsan]: Fix GNU version of strerror_r interceptor

GNU version of strerror_r returns a result pointer that doesn't match the input
buffer. The result pointer is in fact a pointer to some internal storage.
TSAN was recording a write to this location, which was incorrect.

Fixed https://github.com/google/sanitizers/issues/696

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@304858 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 18 insertions, 0 deletions

diff --git a/test/msan/Linux/strerror_r.cc b/test/msan/Linux/strerror_r.cc
new file mode 100644
index 000000000..aec653f9c
--- /dev/null
+++ b/test/msan/Linux/strerror_r.cc
@@ -0,0 +1,18 @@
+// RUN: %clang_msan -O0 -g %s -o %t && %run %t
+
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+
+int main() {
+  char buf[1000];
+  char *res = strerror_r(EINVAL, buf, sizeof(buf));
+  assert(res);
+  volatile int z = strlen(res);
+
+  res = strerror_r(-1, buf, sizeof(buf));
+  assert(res);
+  z = strlen(res);
+
+  return 0;
+}