From: Michael Droettboom <mdboom@gmail.com>
Date: Fri, 6 May 2022 03:59:45 +0000 (-0400)
Subject: gh-92356: Fix regression in ctypes function call overhead (#92357)
X-Git-Tag: v3.11.0b1~24
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=adcb6a6055c7fe6e02621f66945be237b42e945a;p=thirdparty%2FPython%2Fcpython.git

gh-92356: Fix regression in ctypes function call overhead (#92357)

38f331d introduced a delayed initialization routine to set up
ctypes formattable (`_ctypes_init_fielddesc`), but inadvertently
removed setting the `initialization` flag to 1 to avoid initting
each time.
---

diff --git a/Misc/NEWS.d/next/Library/2022-05-05-19-25-09.gh-issue-92356.uvxWdu.rst b/Misc/NEWS.d/next/Library/2022-05-05-19-25-09.gh-issue-92356.uvxWdu.rst
new file mode 100644
index 000000000000..9c9566e5b9d7
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2022-05-05-19-25-09.gh-issue-92356.uvxWdu.rst
@@ -0,0 +1 @@
+Fixed a performance regression in ctypes function calls.
diff --git a/Modules/_ctypes/cfield.c b/Modules/_ctypes/cfield.c
index 23c11c98b2af..c7234fbb18a0 100644
--- a/Modules/_ctypes/cfield.c
+++ b/Modules/_ctypes/cfield.c
@@ -1602,6 +1602,7 @@ _ctypes_get_fielddesc(const char *fmt)
     struct fielddesc *table = formattable;
 
     if (!initialized) {
+        initialized = 1;
         _ctypes_init_fielddesc();
     }