From: Victor Stinner <vstinner@python.org>
Date: Tue, 25 Jul 2023 12:27:48 +0000 (+0200)
Subject: gh-105059: Use GCC/clang extension for PyObject union (#107232)
X-Git-Tag: v3.13.0a1~1216
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=6261585d63a31835b65d445d99dc14cca3fe9cf5;p=thirdparty%2FPython%2Fcpython.git

gh-105059: Use GCC/clang extension for PyObject union (#107232)

Anonymous union is new in C11. To prevent compiler warning
when using -pedantic compiler option, use Clang and GCC
extension on C99 and older.
---

diff --git a/Include/object.h b/Include/object.h
index 7182eba3adfe..2488d6cd0d40 100644
--- a/Include/object.h
+++ b/Include/object.h
@@ -165,6 +165,11 @@ check by comparing the reference count field to the immortality reference count.
  */
 struct _object {
     _PyObject_HEAD_EXTRA
+#if (defined(__GNUC__) || defined(__clang__)) \
+        && !(defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L)
+    // On C99 and older, anonymous union is a GCC and clang extension
+    __extension__
+#endif
     union {
        Py_ssize_t ob_refcnt;
 #if SIZEOF_VOID_P > 4