@@ -0,0 +1,3 @@
+On macOS, do not attempt to use the :manpage:`dup3(2)` and
+:manpage:`pipe2(2)` system calls introduced in
+macOS 27 to prevent problems when running on older systems.
@@ -5282,7 +5282,13 @@ fi
 # header definition prevents usage - autoconf doesn't use the headers), or
 # raise an error if used at runtime. Force these symbols off.
 if test "$ac_sys_system" != "iOS" ; then
-  AC_CHECK_FUNCS([dup3 getentropy getgroups pipe2 system])
+  AC_CHECK_FUNCS([getentropy getgroups system])
+fi
+# In addition, macOS introduced dup3 and pipe2 in macOS 27, late in the
+# lifetime of this version of Python. Rather than adding weaklinking
+# support for them, just continue to ignore them.
+if test "$ac_sys_system" != "iOS" -a "$ac_sys_system" != "Darwin"; then
+  AC_CHECK_FUNCS([dup3 pipe2])
 fi
 
 AC_CHECK_DECL([dirfd],
Original file line number	Diff line number	Diff line change
@@ -0,0 +1,3 @@
	1	+ On macOS, do not attempt to use the :manpage:`dup3(2)` and
	2	+ :manpage:`pipe2(2)` system calls introduced in
	3	+ macOS 27 to prevent problems when running on older systems.