Annotate more functions with _Printf_format_string_

base/strings/string_util.h

Index: base/strings/string_util.h
diff --git a/base/strings/string_util.h b/base/strings/string_util.h
index 169726bca5a128e05c2585d6947003e7f792a5be..3ac44353c6ea43b2c91d72056f80f827955f43fe 100644
--- a/base/strings/string_util.h
+++ b/base/strings/string_util.h
@@ -36,9 +36,14 @@ int vsnprintf(char* buffer, size_t size, const char* format, va_list arguments)
 
 // We separate the declaration from the implementation of this inline
 // function just so the PRINTF_FORMAT works.
-inline int snprintf(char* buffer, size_t size, const char* format, ...)
-    PRINTF_FORMAT(3, 4);
-inline int snprintf(char* buffer, size_t size, const char* format, ...) {
+inline int snprintf(char* buffer,
+                    size_t size,
+                    _Printf_format_string_ const char* format,
+                    ...) PRINTF_FORMAT(3, 4);
+inline int snprintf(char* buffer,
+                    size_t size,
+                    _Printf_format_string_ const char* format,
+                    ...) {
   va_list arguments;
   va_start(arguments, format);
   int result = vsnprintf(buffer, size, format, arguments);