Minor zlib configuration tweaks.

* configure.ac (HAVE_ZLIB): Don't assume zlib is linked if PNG is.
* src/decompress.c (fn_inflateInit2) [!WINDOWSNT]:
Don't assume presence of fn_inflateInit2_ zlib internal function.

4 files changed, 21 insertions, 19 deletions

diff --git a/ChangeLog b/ChangeLog
index 641cbefce20..f579c5226f1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2013-08-12  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Minor zlib configuration tweaks.
+        * configure.ac (HAVE_ZLIB): Don't assume zlib is linked if PNG is.
+
 2013-08-12  Eli Zaretskii  <eliz@gnu.org>
 
         * configure.ac (LIBZ): Comment on w32 peculiarities regarding LIBZ.
diff --git a/configure.ac b/configure.ac
index 5daf84be2ba..b6c7dacd997 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2946,21 +2946,12 @@ AC_SUBST(LIBPNG)
 HAVE_ZLIB=no
 LIBZ=
 if test "${with_zlib}" != "no"; then
-  if test "${HAVE_PNG}" = "yes"; then
-    ### PNG depends on zlib, so if we have PNG, we have zlib.
-    ### Note: w32 does not link against libpng, but instead loads it
-    ### dynamically, but it also does the same with zlib.  So it is OK
-    ### not to have -lz in LIBZ on w32.
-    HAVE_ZLIB=yes
-  else
-    ### No PNG, so check zlib ourselves.
-    OLIBS=$LIBS
-    AC_SEARCH_LIBS([inflateEnd], [z], [HAVE_ZLIB=yes])
-    LIBS=$OLIBS
-    case $ac_cv_search_inflateEnd in
-      -*) LIBZ=$ac_cv_search_inflateEnd ;;
-    esac
-  fi
+  OLIBS=$LIBS
+  AC_SEARCH_LIBS([inflateEnd], [z], [HAVE_ZLIB=yes])
+  LIBS=$OLIBS
+  case $ac_cv_search_inflateEnd in
+    -*) LIBZ=$ac_cv_search_inflateEnd ;;
+  esac
 fi
 if test "${HAVE_ZLIB}" = "yes"; then
   AC_DEFINE([HAVE_ZLIB], 1, [Define to 1 if you have the zlib library (-lz).])
diff --git a/src/ChangeLog b/src/ChangeLog
index 3a8fcfe7e9c..cf851d5bec0 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,9 @@
+2013-08-12  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Minor zlib configuration tweaks.
+        * decompress.c (fn_inflateInit2) [!WINDOWSNT]:
+        Don't assume presence of fn_inflateInit2_ zlib internal function.
+
 2013-08-12  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
         * decompress.c (Fzlib_decompress_gzipped_region): Rename to
diff --git a/src/decompress.c b/src/decompress.c
index 3605d446e5a..4e4e3a9c7dc 100644
--- a/src/decompress.c
+++ b/src/decompress.c
@@ -67,17 +67,17 @@ init_zlib_functions (void)
   return 1;
 }
 
+#define fn_inflateInit2(strm, windowBits) \
+        fn_inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
+
 #else /* !WINDOWSNT */
 
-#define fn_inflateInit2_        inflateInit2_
+#define fn_inflateInit2         inflateInit2
 #define fn_inflate              inflate
 #define fn_inflateEnd           inflateEnd
 
 #endif  /* WINDOWSNT */
 
-#define fn_inflateInit2(strm, windowBits) \
-        fn_inflateInit2_((strm), (windowBits), ZLIB_VERSION, sizeof(z_stream))
-
 
 struct decompress_unwind_data
 {