Re: Enable -Wstrict-prototypes and -Wold-style-definition by default

Andres Freund <andres@anarazel.de>

From: Andres Freund <andres@anarazel.de>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Nazir Bilal Yavuz <byavuz81@gmail.com>, Peter Eisentraut <peter@eisentraut.org>, Bertrand Drouvot <bertranddrouvot.pg@gmail.com>, pgsql-hackers@lists.postgresql.org
Date: 2026-03-18T17:26:26Z
Lists: pgsql-hackers
Hi,

On 2026-03-18 13:03:03 -0400, Tom Lane wrote:
> Nazir Bilal Yavuz <byavuz81@gmail.com> writes:
> > I got this warning while running headerscheck after this commit:
> 
> > ~/Desktop/projects/postgres/src/interfaces/ecpg/ecpglib/ecpglib_extern.h:221:40:
> > warning: function declaration isn’t a prototype [-Wstrict-prototypes]
> >   221 | void            ecpg_init_sqlca(struct sqlca_t *sqlca)
> 
> Yeah, I see that too.  I believe the problem is that headerscheck
> doesn't cause POSTGRES_ECPG_INTERNAL to become defined, so that
> what the compiler is seeing is (from sqlca.h):
> 
> 	#ifndef POSTGRES_ECPG_INTERNAL
> 	#define sqlca (*ECPGget_sqlca())
> 	#endif
> 
> and then
> 
> 	void		ecpg_init_sqlca(struct sqlca_t *sqlca);
> 
> Kinda surprising that that's not a syntax error.

Indeed.


I don't even really understand what that POSTGRES_ECPG_INTERNAL business is
about. Is that really just so we can use a local "sqlca" variable in some of
our own ecpglib code while code using ecpg can't do that?  Please tell me it
ain't so.


> We could plausibly fix this either by
> 
> (1) renaming ecpg_init_sqlca's parameter to something else;
> 
> (2) ensuring that POSTGRES_ECPG_INTERNAL is defined.  I'd be inclined
> to make ecpglib_extern.h do that rather than expecting headerscheck
> to know about it.

> Neither of these options are beautiful, but perhaps #1 is slightly
> less ugly.  Any preferences?

1) seems to be the preferrable approach. It's what code using ecpg already has
to do, right?

Greetings,

Andres Freund



Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Add warning option -Wold-style-declaration

  2. configure: Apply -Werror=vla to C++ as well as C

  3. Enable warning like -Wstrict-prototypes on MSVC as well

  4. Remove compiler warning option -Wendif-labels

  5. Disable warnings in system headers in MSVC

  6. Fix -Wstrict-prototypes warning in ecpg_init_sqlca() declaration.