From be70b86c5764b296f7ad75cf91f2e0b4c3d7cfe8 Mon Sep 17 00:00:00 2001
From: James Zern <jzern@google.com>
Date: Tue, 9 Sep 2014 22:55:29 -0700
Subject: [PATCH] configure: simplify libpng-config invocation

use --ldflags over --prefix + --libs combination

based on comment in issue #180.

Change-Id: If2ca06053d5237b6722ddf4117917e5f3c06ab59
---
 configure.ac | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/configure.ac b/configure.ac
index 4f1ef58d..a472d270 100644
--- a/configure.ac
+++ b/configure.ac
@@ -296,15 +296,12 @@ AC_ARG_ENABLE([png], AS_HELP_STRING([--disable-png],
                                      @<:@default=auto@:>@]))
 AS_IF([test "x$enable_png" != "xno"], [
   CLEAR_LIBVARS([PNG])
-  AC_PATH_PROGS(LIBPNG_CONFIG,
-                [libpng-config libpng15-config libpng14-config libpng12-config])
+  AC_PATH_PROGS([LIBPNG_CONFIG],
+                [libpng-config libpng16-config libpng15-config libpng14-config \
+                 libpng12-config])
   if test -n "$LIBPNG_CONFIG"; then
     PNG_INCLUDES=`$LIBPNG_CONFIG --cflags`
-    PNG_PREFIX=`$LIBPNG_CONFIG --prefix`
-    if test "${PNG_PREFIX}/lib" != "/usr/lib" ; then
-      PNG_LIBS="-L${PNG_PREFIX}/lib"
-    fi
-    PNG_LIBS="$PNG_LIBS `$LIBPNG_CONFIG --libs`"
+    PNG_LIBS="`$LIBPNG_CONFIG --ldflags`"
   fi
 
   WITHLIB_OPTION([png], [PNG])