Re: Use "?=" operator for a contrib makefile in documentation

Marina Polyakova <m.polyakova@postgrespro.ru>

From: Marina Polyakova <m.polyakova@postgrespro.ru>
To: Peter Eisentraut <peter@eisentraut.org>
Cc: Maxim Orlov <orlovmg@gmail.com>, Postgres hackers <pgsql-hackers@lists.postgresql.org>
Date: 2025-10-02T05:39:02Z
Lists: pgsql-hackers
Hello!

We use common scripts to check various PostgreSQL modules with various 
PostgreSQL major versions. It is easier to set the required PG_CONFIG in 
the enviroment than to change various make commands. In particular, they 
are quite common if we want to build, install or run installcheck in a 
specific directory. The PATH enviroment variable also works, but 
PG_CONFIG is usually sufficient and we want to be sure of that.

On 2025-09-29 15:50, Peter Eisentraut wrote:
> I think the current text is preferable.  This allows running
> 
> make PG_CONFIG=...
> 
> so that you can pick a different PostgreSQL installation for a 
> particular build.
> 
> If you always want to use a particular PostgreSQL installation, then 
> you could alter the PATH in the environment.
> 
> I don't know that there is a use case of setting only PG_CONFIG in the 
> environment that is not covered by these other two approaches.

-- 
Marina Polyakova
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company