Hi!
I've noticed that while for requires keyword we have a diagnostics like
error_at (cp_lexer_peek_token (parser->lexer)->location,
"%<requires%> only available with "
"%<-std=c++2a%> or %<-fconcepts%>");
for concept keyword we emit
inform (location, "%<concept%> only available with %<-fconcepts%>");
The following patch adjusts the latter to match the former, because I think
more people will use -std=c++2a than -fconcepts in the GCC 10 timeframe.
Tested on x86_64-linux, ok for trunk?
2019-12-06 Jakub Jelinek <ja...@redhat.com>
* parser.c (cp_parser_diagnose_invalid_type_name): Mention
that concept is also available with -std=c++2a.
--- gcc/cp/parser.c.jj 2019-12-05 10:03:04.072181899 +0100
+++ gcc/cp/parser.c 2019-12-06 19:40:44.090311079 +0100
@@ -3367,7 +3367,8 @@ cp_parser_diagnose_invalid_type_name (cp
inform (location, "C++20 %<constinit%> only available with "
"%<-std=c++2a%> or %<-std=gnu++2a%>");
else if (!flag_concepts && id == ridpointers[(int)RID_CONCEPT])
- inform (location, "%<concept%> only available with %<-fconcepts%>");
+ inform (location, "%<concept%> only available with %<-std=c++2a%> or "
+ "%<-fconcepts%>");
else if (processing_template_decl && current_class_type
&& TYPE_BINFO (current_class_type))
{
Jakub
