Re: headerscheck: Avoid mutual inclusion of pg_config.h and c.h

On 23.03.26 09:50, Peter Eisentraut wrote:
> Headers that c.h includes early should not have another header included
> before them in the headerscheck test file, especially not c.h.
>
> A particular instance of a problem is that pg_config.h defines some
> symbols that c.h later undefines in some cases, such as in the code
> added by commit cd083b54bd67, but there were also some before that. This
> only works correctly if pg_config.h is included first.
>
> This problem can currently be observed on CI.
>
> pg_config_manual.h and pg_config_os.h are closely related to pg_config.h
> and should be treated the same way.
>
> postgres_ext.h is meant to be usable standalone, so testing it with c.h
> included first defeats the point.
>
> c.h also includes port.h, but this patch leaves that alone, since port.h
> does need some of c.h to be processed first.  (But because of header
> guards, testing port.h separately is probably ineffective.)

This has been committed.