diff --git a/format.h b/format.h
index 0af01439..8c61a8ba 100644
--- a/format.h
+++ b/format.h
@@ -61,6 +61,7 @@
 #endif
 
 #ifdef __clang__
+# define FMT_CLANG_VERSION (__clang_major__ * 100 + __clang_minor__)
 # pragma clang diagnostic ignored "-Wdocumentation-unknown-command"
 #endif
 
@@ -119,7 +120,8 @@
 # define FMT_NOEXCEPT(expr)
 #endif
 
-#if FMT_HAS_CPP_ATTRIBUTE(clang::fallthrough)
+#if FMT_HAS_CPP_ATTRIBUTE(clang::fallthrough) || \
+  (FMT_CLANG_VERSION >= 600 && __cplusplus >= 201103)
 # define FMT_FALLTHROUGH [[clang::fallthrough]]
 #else
 # define FMT_FALLTHROUGH