libtool2: macOS 11 support

pkgs/development/tools/misc/libtool/libtool2-macos11.patch

@@ -0,0 +1,32 @@
+Signed-off-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com>
+---
+ m4/libtool.m4 | 13 ++++---------
+ 1 file changed, 4 insertions(+), 9 deletions(-)
+
+diff --git a/m4/libtool.m4 b/m4/libtool.m4
+index f2d1f398..b971e8e7 100644
+--- a/m4/libtool.m4
++++ b/m4/libtool.m4
+@@ -1067,16 +1067,11 @@ _LT_EOF
+       _lt_dar_allow_undefined='$wl-undefined ${wl}suppress' ;;
+     darwin1.*)
+       _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
+-    darwin*) # darwin 5.x on
+-      # if running on 10.5 or later, the deployment target defaults
+-      # to the OS version, if on x86, and 10.4, the deployment
+-      # target defaults to 10.4. Don't you love it?
+-      case ${MACOSX_DEPLOYMENT_TARGET-10.0},$host in
+-	10.0,*86*-darwin8*|10.0,*-darwin[[91]]*)
+-	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
+-	10.[[012]][[,.]]*)
++    darwin*)
++      case ${MACOSX_DEPLOYMENT_TARGET},$host in
++	10.[[012]],*|,*powerpc*)
+ 	  _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
+-	10.*)
++	*)
+ 	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
+       esac
+     ;;
+-- 
+2.24.3 (Apple Git-128)

pkgs/development/tools/misc/libtool/libtool2.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchurl, m4, perl, help2man
+{ lib, stdenv, fetchurl, fetchpatch, autoconf, automake, m4, perl, help2man
 }:
 
 stdenv.mkDerivation rec {
@@ -12,7 +12,26 @@ stdenv.mkDerivation rec {
 
   outputs = [ "out" "lib" ];
 
-  nativeBuildInputs = [ perl help2man m4 ];
+  patches = [
+    # Suport macOS version 11.0
+    # https://lists.gnu.org/archive/html/libtool-patches/2020-06/msg00001.html
+    ./libtool2-macos11.patch
+  ];
+
+  # Normally we'd use autoreconfHook, but that includes libtoolize.
+  postPatch = ''
+    aclocal -I m4
+    automake
+    autoconf
+
+    pushd libltdl
+    aclocal -I ../m4
+    automake
+    autoconf
+    popd
+  '';
+
+  nativeBuildInputs = [ perl help2man m4 ] ++ [ autoconf automake ];
   propagatedBuildInputs = [ m4 ];
 
   # Don't fixup "#! /bin/sh" in Libtool, otherwise it will use the