Disable gnu-string-literal-operator-template warning

CMakeLists.txt

@@ -111,14 +111,6 @@ if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
     set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS}
         -Wno-zero-as-null-pointer-constant)
   endif ()
-
-endif ()
-
-check_cxx_compiler_flag(
-  -Wno-gnu-string-literal-operator-template HAS_GNU_UDL_WARNING)
-if (HAS_GNU_UDL_WARNING)
-  set(PEDANTIC_COMPILE_FLAGS ${PEDANTIC_COMPILE_FLAGS}
-      -Wno-gnu-string-literal-operator-template)
 endif ()
 
 if (MSVC)

include/fmt/format.h

@@ -65,6 +65,10 @@
 # pragma GCC diagnostic ignored "-Wsign-conversion"
 #endif
 
+# if FMT_CLANG_VERSION
+#  pragma GCC diagnostic ignored "-Wgnu-string-literal-operator-template"
+# endif
+
 #ifdef _SECURE_SCL
 # define FMT_SECURE_SCL _SECURE_SCL
 #else