$NetBSD: patch-configure.ac,v 1.1 2020/11/17 19:33:26 sjmulder Exp $

Support for macOS 11 and Apple Silicon (ARM). Mostly backported from:
https://github.com/python/cpython/pull/22855

--- configure.ac.orig	2020-08-15 05:20:16.000000000 +0000
+++ configure.ac
@@ -212,7 +212,11 @@ fi
 AC_SUBST(LIPO_32BIT_FLAGS)
 AC_MSG_CHECKING(for --with-universal-archs)
 AC_ARG_WITH(universal-archs,
-    AS_HELP_STRING([--with-universal-archs=ARCH], [select architectures for universal build ("32-bit", "64-bit", "3-way", "intel", "intel-32", "intel-64", or "all")]),
+    AS_HELP_STRING([--with-universal-archs=ARCH],
+                   [specify the kind of universal binary that should be created. this option is
+                    only valid when --enable-universalsdk is set; options are:
+                    ("universal2", "32-bit", "64-bit", "3-way", "intel", "intel-32", "intel-64", or "all")
+                    see Mac/README.rst]),
 [
 	UNIVERSAL_ARCHS="$withval"
 ],
@@ -1557,7 +1561,7 @@ AC_SUBST(BASECFLAGS)
 AC_SUBST(CFLAGS_NODIST)
 AC_SUBST(LDFLAGS_NODIST)
 
-# The -arch flags for universal builds on OSX
+# The -arch flags for universal builds on macOS
 UNIVERSAL_ARCH_FLAGS=
 AC_SUBST(UNIVERSAL_ARCH_FLAGS)
 
@@ -1859,6 +1863,11 @@ yes)
                LIPO_32BIT_FLAGS="-extract ppc7400 -extract i386"
                ARCH_RUN_32BIT="/usr/bin/arch -i386 -ppc"
                ;;
+            universal2)
+               UNIVERSAL_ARCH_FLAGS="-arch arm64 -arch x86_64"
+               LIPO_32BIT_FLAGS=""
+               ARCH_RUN_32BIT="true"
+		;;
             intel)
                UNIVERSAL_ARCH_FLAGS="-arch i386 -arch x86_64"
                LIPO_32BIT_FLAGS="-extract i386"
@@ -2455,6 +2464,9 @@ case $ac_sys_system/$ac_sys_release in
     		;;
     	ppc)
     		MACOSX_DEFAULT_ARCH="ppc64"
+		;;
+    	arm64)
+    		MACOSX_DEFAULT_ARCH="arm64"
     		;;
     	arm64)
     		MACOSX_DEFAULT_ARCH="arm64"
@@ -3677,6 +3689,12 @@ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
    AC_MSG_RESULT(yes)],
   [AC_MSG_RESULT(no)
 ])
+AC_MSG_CHECKING(for _dyld_shared_cache_contains_path)
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <mach-o/dyld.h>]], [[void *x=_dyld_shared_cache_contains_path]])],
+  [AC_DEFINE(HAVE_DYLD_SHARED_CACHE_CONTAINS_PATH, 1, Define if you have the '_dyld_shared_cache_contains_path' function.)
+   AC_MSG_RESULT(yes)],
+  [AC_MSG_RESULT(no)
+])
 
 # On some systems (eg. FreeBSD 5), we would find a definition of the
 # functions ctermid_r, setgroups in the library, but no prototype