Re: [PATCH] c++/modules: relax diagnostic about GMF contents

[Jason Merrill <jason@redhat.com>]

On 2/15/24 16:10, Patrick Palka wrote:
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look
> OK for trunk?
> 
> -- >8 --
> 
> Issuing a hard error when the GMF doesn't contain preprocessing
> directives is inconvenient for automated testcase reduction via cvise.
> This patch relaxes this diagnostic into a pedwarn.
> 
> gcc/cp/ChangeLog:
> 
> 	* parser.cc (cp_parser_translation_unit): Relax GMF contents
> 	error into a pedwarn.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* g++.dg/modules/friend-6_a.C: Remove now unnecessary
> 	preprocessing directives from GMF.
> ---
>   gcc/cp/parser.cc                          | 6 +++---
>   gcc/testsuite/g++.dg/modules/friend-6_a.C | 2 --
>   2 files changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc
> index 9d0914435fb..e60f0425035 100644
> --- a/gcc/cp/parser.cc
> +++ b/gcc/cp/parser.cc
> @@ -5253,9 +5253,9 @@ cp_parser_translation_unit (cp_parser* parser)
>   	      if (!warned)
>   		{
>   		  warned = true;
> -		  error_at (token->location,
> -			    "global module fragment contents must be"
> -			    " from preprocessor inclusion");
> +		  pedwarn (token->location, OPT_Wpedantic,
> +			   "global module fragment contents must be"
> +			   " from preprocessor inclusion");

Relaxing to pedwarn is fine, but I think it should be on by default, not 
just with -pedantic.  So it should get a new option.

Jason