From b7c7ed184df62a20040386ef935f3dc6495dd877 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <sezeroz@gmail.com>
Date: Sun, 14 Oct 2018 17:00:00 +0300
Subject: [PATCH] backport fix for bug 1754 (need the Objective C runtime for
 ImageIo.m.)

(default 2.0 branch commits 361ab0371a02; 56243a3eb8ea along with it..)
---
 configure    | 13 +++++++++----
 configure.in | 11 +++++++----
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/configure b/configure
index e8efe2f3..67585ed1 100755
--- a/configure
+++ b/configure
@@ -12963,7 +12963,7 @@ else
 fi
 
         if test x$enable_imageio = xyes; then
-            IMG_LIBS="-Wl,-framework,ApplicationServices $IMG_LIBS"
+            IMG_LIBS="-Wl,-framework,ApplicationServices -lobjc $IMG_LIBS"
         else
             CFLAGS="$CFLAGS -DSDL_IMAGE_USE_COMMON_BACKEND"
         fi
@@ -13658,7 +13658,12 @@ else
 fi
 
 
-if test x$enable_jpg = xyes || test x$enable_tif = xyes; then
+{ $as_echo "$as_me:$LINENO: checking for ImageIO support" >&5
+$as_echo_n "checking for ImageIO support... " >&6; }
+{ $as_echo "$as_me:$LINENO: result: $enable_imageio" >&5
+$as_echo "$enable_imageio" >&6; }
+
+if (test x$enable_jpg = xyes || test x$enable_tif = xyes) && test x$enable_imageio != xyes; then
     if test "${ac_cv_header_jpeglib_h+set}" = set; then
   { $as_echo "$as_me:$LINENO: checking for jpeglib.h" >&5
 $as_echo_n "checking for jpeglib.h... " >&6; }
@@ -13891,7 +13896,7 @@ $as_echo "$as_me: WARNING: JPG image loading disabled" >&2;}
     fi
 fi
 
-if test "x$enable_png" = xyes; then
+if test x$enable_png = xyes -a x$enable_imageio != xyes; then
 
 pkg_failed=no
 { $as_echo "$as_me:$LINENO: checking for LIBPNG" >&5
@@ -14407,7 +14412,7 @@ $as_echo "$as_me: WARNING: PNG image loading disabled" >&2;}
     fi
 fi
 
-if test x$enable_tif = xyes; then
+if test x$enable_tif = xyes -a x$enable_imageio != xyes; then
     if test "${ac_cv_header_tiffio_h+set}" = set; then
   { $as_echo "$as_me:$LINENO: checking for tiffio.h" >&5
 $as_echo_n "checking for tiffio.h... " >&6; }
diff --git a/configure.in b/configure.in
index 33be0833..7fe4d970 100644
--- a/configure.in
+++ b/configure.in
@@ -79,8 +79,11 @@ case "$host" in
     *-*-darwin*)
         AC_ARG_ENABLE([imageio], [AC_HELP_STRING([--enable-imageio], [use native Mac OS X frameworks for loading images [default=yes]])],
                       [], [enable_imageio=yes])
+        dnl Show a message when we use ImageIO support so it's not a surprise
+        AC_MSG_CHECKING([for ImageIO support])
+        AC_MSG_RESULT($enable_imageio)
         if test x$enable_imageio = xyes; then
-            IMG_LIBS="-Wl,-framework,ApplicationServices $IMG_LIBS"
+            IMG_LIBS="-Wl,-framework,ApplicationServices -lobjc $IMG_LIBS"
         else
             CFLAGS="$CFLAGS -DSDL_IMAGE_USE_COMMON_BACKEND"
         fi
@@ -159,7 +162,7 @@ AC_ARG_ENABLE([webp], [AC_HELP_STRING([--enable-webp], [support loading WEBP ima
 AC_ARG_ENABLE([webp-shared], AC_HELP_STRING([--enable-webp-shared], [dynamically load WEBP support [[default=yes]]]),
  [], [enable_webp_shared=yes])
 
-if test x$enable_jpg = xyes || test x$enable_tif = xyes; then
+if (test x$enable_jpg = xyes || test x$enable_tif = xyes) && test x$enable_imageio != xyes; then
     AC_CHECK_HEADER([jpeglib.h], [have_jpg_hdr=yes])
     AC_CHECK_LIB([jpeg], [jpeg_CreateDecompress], [have_jpg_lib=yes])
     if test x$have_jpg_hdr = xyes -a x$have_jpg_lib = xyes; then
@@ -188,7 +191,7 @@ if test x$enable_jpg = xyes || test x$enable_tif = xyes; then
     fi
 fi
 
-if test "x$enable_png" = xyes; then
+if test x$enable_png = xyes -a x$enable_imageio != xyes; then
     PKG_CHECK_MODULES([LIBPNG], [libpng], [dnl
         have_png_hdr=yes
         have_png_lib=yes
@@ -225,7 +228,7 @@ if test "x$enable_png" = xyes; then
     fi
 fi
 
-if test x$enable_tif = xyes; then
+if test x$enable_tif = xyes -a x$enable_imageio != xyes; then
     AC_CHECK_HEADER([tiffio.h], [have_tif_hdr=yes])
     AC_CHECK_LIB([tiff], [TIFFClientOpen], [have_tif_lib=yes], [], [-lz])
     if test x$have_tif_hdr = xyes -a x$have_tif_lib = xyes; then