$NetBSD: patch-configure,v 1.5 2022/07/27 18:32:11 wiz Exp $

Fix png library name.

--- configure.orig	2022-06-30 09:26:31.000000000 +0000
+++ configure
@@ -29988,13 +29988,13 @@ if test "$with_png" = "no" ; then
 
 elif test "$with_png" = "yes" -o "$with_png" = "" ; then
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for png_set_IHDR in -lpng" >&5
-$as_echo_n "checking for png_set_IHDR in -lpng... " >&6; }
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for png_set_IHDR in -lpng16" >&5
+$as_echo_n "checking for png_set_IHDR in -lpng16... " >&6; }
 if ${ac_cv_lib_png_png_set_IHDR+:} false; then :
   $as_echo_n "(cached) " >&6
 else
   ac_check_lib_save_LIBS=$LIBS
-LIBS="-lpng $LIBS $LIBS"
+LIBS="-lpng16 $LIBS $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
@@ -30047,7 +30047,7 @@ done
     PNG_SETTING=internal
   fi
   if test "$PNG_SETTING" = "external" ; then
-    LIBS="-lpng $LIBS"
+    LIBS="-lpng16 $LIBS"
     echo "using pre-installed libpng."
   else
     echo "using internal png code."
@@ -30062,7 +30062,7 @@ elif test "$with_png" = "internal" ; the
 else
 
   PNG_SETTING=external
-  LIBS="-L$with_png -L$with_png/lib -lpng $LIBS"
+  LIBS="-L$with_png -L$with_png/lib -lpng16 $LIBS"
   EXTRA_INCLUDES="-I$with_png -I$with_png/include $EXTRA_INCLUDES"
 
   echo "using libpng from $with_png."
@@ -39039,7 +39039,7 @@ if test "$with_pdfium" != "no" -a "$with
         PDFIUM_LIB="-L$with_pdfium/lib -lpdfium"
     fi
 
-    PDFIUM_LIB="$PDFIUM_LIB -lopenjp2 -ljpeg -lpng -lz -llcms2 -lpthread -lm -lstdc++"
+    PDFIUM_LIB="$PDFIUM_LIB -lopenjp2 -ljpeg -lpng16 -lz -llcms2 -lpthread -lm -lstdc++"
 
     if test ! -z "`uname | grep Darwin`" ; then
         PDFIUM_LIB="-stdlib=libstdc++ $PDFIUM_LIB"