[ASan] Define an internal implementation of strchr to make stack OOB tests pass on Windows

llvm-svn: 150499

compiler-rt/lib/asan/asan_interceptors.cc

@@ -120,6 +120,16 @@ size_t internal_strnlen(const char *s, size_t maxlen) {
   return i;
 }
 
+char* internal_strchr(const char *s, int c) {
+  while (true) {
+    if (*s == (char)c)
+      return (char*)s;
+    if (*s == 0)
+      return NULL;
+    s++;
+  }
+}
+
 void* internal_memchr(const void* s, int c, size_t n) {
   const char* t = (char*)s;
   for (size_t i = 0; i < n; ++i, ++t)

compiler-rt/lib/asan/asan_interceptors.h

@@ -33,6 +33,7 @@ namespace __asan {
 // __asan::internal_X() is the implementation of X() for use in RTL.
 size_t internal_strlen(const char *s);
 size_t internal_strnlen(const char *s, size_t maxlen);
+char* internal_strchr(const char *s, int c);
 void* internal_memchr(const void* s, int c, size_t n);
 int internal_memcmp(const void* s1, const void* s2, size_t n);
 char *internal_strstr(const char *haystack, const char *needle);

compiler-rt/lib/asan/asan_rtl.cc

@@ -159,7 +159,7 @@ static bool DescribeStackAddress(uintptr_t addr, uintptr_t access_size) {
   // where alloc_i looks like "offset size len ObjectName ".
   CHECK(frame_descr);
   // Report the function name and the offset.
-  const char *name_end = REAL(strchr)(frame_descr, ' ');
+  const char *name_end = internal_strchr(frame_descr, ' ');
   CHECK(name_end);
   buf[0] = 0;
   internal_strncat(buf, frame_descr,