From d561cb47a76ea0563721809dfbd4f717741f21ca Mon Sep 17 00:00:00 2001
From: Jack Andersen <jackoalan@gmail.com>
Date: Sun, 14 Jul 2019 19:04:37 -1000
Subject: [PATCH] Opt-in macro to enforce use of compile-time format strings

---
 include/fmt/core.h | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/fmt/core.h b/include/fmt/core.h
index 632b7dfe..de398d29 100644
--- a/include/fmt/core.h
+++ b/include/fmt/core.h
@@ -1258,7 +1258,13 @@ template <typename T, typename Char> struct named_arg : named_arg_base<Char> {
 };
 
 template <typename..., typename S, FMT_ENABLE_IF(!is_compile_string<S>::value)>
-inline void check_format_string(const S&) {}
+inline void check_format_string(const S&) {
+#if defined(FMT_ENFORCE_COMPILE_STRING)
+  static_assert(is_compile_string<S>::value,
+                "FMT_ENFORCE_COMPILE_STRING requires all format strings to "
+                "utilize FMT_STRING() or fmt().");
+#endif
+}
 template <typename..., typename S, FMT_ENABLE_IF(is_compile_string<S>::value)>
 void check_format_string(S);