[Emacs-diffs] emacs-24 r117043: * configure.ac (LIBPNG): Consult libpng-config

[Glenn Morris]

------------------------------------------------------------
revno: 117043
revision-id: address@hidden
parent: address@hidden
fixes bug: http://debbugs.gnu.org/17339
committer: Glenn Morris <address@hidden>
branch nick: emacs-24
timestamp: Thu 2014-05-01 17:57:27 -0400
message:
  * configure.ac (LIBPNG): Consult libpng-config
  for the precise form of "-lpng" to use.
modified:
  ChangeLog                      changelog-20091113204419-o5vbwnq5f7feedwu-1538
  configure.ac                   
configure.in-20091113204419-o5vbwnq5f7feedwu-783

=== modified file 'ChangeLog'
--- a/ChangeLog 2014-04-29 14:49:11 +0000
+++ b/ChangeLog 2014-05-01 21:57:27 +0000
@@ -1,3 +1,8 @@
+2014-05-01  Glenn Morris  <address@hidden>
+
+       * configure.ac (LIBPNG): Consult libpng-config for the precise
+       form of "-lpng" to use.  (Bug#17339)
+
 2014-04-29  Glenn Morris  <address@hidden>
 
        * configure.ac: Treat MirBSD as OpenBSD.  (Bug#17339)

=== modified file 'configure.ac'
--- a/configure.ac      2014-04-29 14:49:11 +0000
+++ b/configure.ac      2014-05-01 21:57:27 +0000
@@ -3101,8 +3101,15 @@
   fi
 
   if test "${HAVE_PNG}" = "yes"; then
-    AC_DEFINE(HAVE_PNG, 1, [Define to 1 if you have the png library (-lpng).])
-    LIBPNG="-lpng -lz -lm"
+    AC_DEFINE(HAVE_PNG, 1, [Define to 1 if you have the png library.])
+
+    dnl Some systems, eg NetBSD 6, only provide eg "libpng16", not "libpng".
+    lpng=`libpng-config --libs 2> /dev/null`
+    case $lpng in
+      -l*) : ;;
+      *) lpng="-lpng" ;;
+    esac
+    LIBPNG="$lpng -lz -lm"
 
     AC_CHECK_DECL(png_longjmp,
       [],
@@ -4976,7 +4983,7 @@
 echo "  Does Emacs use -ljpeg?                                  ${HAVE_JPEG}"
 echo "  Does Emacs use -ltiff?                                  ${HAVE_TIFF}"
 echo "  Does Emacs use a gif library?                           ${HAVE_GIF} 
$LIBGIF"
-echo "  Does Emacs use -lpng?                                   ${HAVE_PNG}"
+echo "  Does Emacs use a png library?                           ${HAVE_PNG} 
$LIBPNG"
 echo "  Does Emacs use -lrsvg-2?                                ${HAVE_RSVG}"
 echo "  Does Emacs use imagemagick?                             
${HAVE_IMAGEMAGICK}"