From: Petr Viktorin <encukou@gmail.com>
Date: Wed, 8 Nov 2017 15:59:20 +0000 (+0100)
Subject: bpo-29179: Document the Py_UNUSED macro (#4341)
X-Git-Tag: v3.7.0a3~207
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=2138163621196a186975796afb2b0a6aa335231d;p=python

bpo-29179: Document the Py_UNUSED macro (#4341)

Py_UNUSED has a public name, and is used in the wild outside CPython,
but was not documented. Rectify that.

The macro was added in bpo-19976 and referenced in bpo-26179.
---

diff --git a/Doc/c-api/intro.rst b/Doc/c-api/intro.rst
index 63231808b4..15006100c7 100644
--- a/Doc/c-api/intro.rst
+++ b/Doc/c-api/intro.rst
@@ -149,6 +149,13 @@ complete listing.
    Like ``getenv(s)``, but returns *NULL* if :option:`-E` was passed on the
    command line (i.e. if ``Py_IgnoreEnvironmentFlag`` is set).
 
+.. c:macro:: Py_UNUSED(arg)
+
+   Use this for unused arguments in a function definition to silence compiler
+   warnings, e.g. ``PyObject* func(PyObject *Py_UNUSED(ignored))``.
+
+   .. versionadded:: 3.4
+
 
 .. _api-objects: