From ca8864e393dfd9e2edce134c8d2901e942b29470 Mon Sep 17 00:00:00 2001
From: Maxim Orlov <orlovmg@gmail.com>
Date: Thu, 25 Sep 2025 16:04:36 +0300
Subject: [PATCH v1] Recommend to use PG_CONFIG from the environment for
 contrib

For a basic example of creating an postgres extension, use the "?="
operator with PG_CONFIG.  It allows you to obtain values from the
environment instead of the command line.

This avoids errors like:

$ PG_CONFIG=... make
make: pg_config: No such file or directory
---
 doc/src/sgml/extend.sgml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/extend.sgml b/doc/src/sgml/extend.sgml
index 63c5ec6d1eb..ccdc45f0a68 100644
--- a/doc/src/sgml/extend.sgml
+++ b/doc/src/sgml/extend.sgml
@@ -1420,7 +1420,7 @@ relocatable = false
 EXTENSION = pair
 DATA = pair--1.0.sql
 
-PG_CONFIG = pg_config
+PG_CONFIG ?= pg_config
 PGXS := $(shell $(PG_CONFIG) --pgxs)
 include $(PGXS)
 </programlisting>
@@ -1480,7 +1480,7 @@ DATA = isbn_issn--1.0.sql
 DOCS = README.isbn_issn
 HEADERS_isbn_issn = isbn_issn.h
 
-PG_CONFIG = pg_config
+PG_CONFIG ?= pg_config
 PGXS := $(shell $(PG_CONFIG) --pgxs)
 include $(PGXS)
 </programlisting>
-- 
2.43.0