$NetBSD: patch-configure.ac,v 1.3 2015/09/14 14:40:37 gdt Exp $

Override EGL detection.

Revert upstream's disabling of glx on Mac.  See
https://github.com/anholt/libepoxy/commit/e3051481cc9f5b7b36b317aff1454ee16ea9cdb9
for context.  We require X11 anyway, and libepoxy without glx is
defective - in particular, gtk3+ fails to build.
Not yet reported upstream.

--- configure.ac.orig	2015-07-15 23:46:36.000000000 +0000
+++ configure.ac
@@ -77,15 +77,16 @@ case $host_os in
         AC_SUBST([LOG_COMPILER], [wine])
         ;;
     darwin*)
+        # TODO: explain why egl is forced off on Darwin
         build_egl=no
-        build_glx=no
+        build_glx=yes
         build_wgl=no
         build_apple=yes
         has_znow=no
         EPOXY_LINK_LIBS=""
         ;;
     *)
-        build_egl=yes
+        build_egl=${PKGSRC_BUILD_EGL}
         build_glx=yes
         build_wgl=no
         # On platforms with dlopen, we load everything dynamically and