From 24edc7225299026bba0d0d4dcfc2c79316337681 Mon Sep 17 00:00:00 2001
From: Chris Marsh <chrismarsh.c2@gmail.com>
Date: Fri, 17 May 2024 10:16:31 -0600
Subject: [PATCH] docs: show phase signature for builders (#44067)

---
 lib/spack/docs/build_systems/autotoolspackage.rst | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/lib/spack/docs/build_systems/autotoolspackage.rst b/lib/spack/docs/build_systems/autotoolspackage.rst
index c0adcda178b..392feb3ed48 100644
--- a/lib/spack/docs/build_systems/autotoolspackage.rst
+++ b/lib/spack/docs/build_systems/autotoolspackage.rst
@@ -147,6 +147,15 @@ example, the ``bash`` shell is used to run the ``autogen.sh`` script.
    def autoreconf(self, spec, prefix):
        which("bash")("autogen.sh")
 
+If the ``package.py`` has build instructions in a separate
+:ref:`builder class <multiple_build_systems>`, the signature for a phase changes slightly:
+
+.. code-block:: python
+
+   class AutotoolsBuilder(AutotoolsBuilder):
+      def autoreconf(self, pkg, spec, prefix):
+         which("bash")("autogen.sh")
+
 """""""""""""""""""""""""""""""""""""""
 patching configure or Makefile.in files
 """""""""""""""""""""""""""""""""""""""