* image.c: Pacify --enable-gcc-warnings.

(GIFLIB_MAJOR, GIFLIB_MINOR, GIFLIB_RELEASE, fn_GifErrorString):
#define only if used.

src/ChangeLog

+2013-10-10  Paul Eggert  <eggert@cs.ucla.edu>
+
+	* image.c: Pacify --enable-gcc-warnings.
+	(GIFLIB_MAJOR, GIFLIB_MINOR, GIFLIB_RELEASE, fn_GifErrorString):
+	#define only if used.
+
 2013-10-10  Eli Zaretskii  <eliz@gnu.org>
 
 	* image.c (GIFLIB_MAJOR): Define to 4 if undefined.

src/image.c

@@ -7203,7 +7203,21 @@ gif_image_p (Lisp_Object object)
 
 #ifdef HAVE_GIF
 
+/* Giflib before 5.0 didn't define these macros.  */
+#ifndef GIFLIB_MAJOR
+#define GIFLIB_MAJOR 4
+#endif
+
 #if defined (HAVE_NTGUI)
+
+/* Giflib before 5.0 didn't define these macros (used only if HAVE_NTGUI).  */
+#ifndef GIFLIB_MINOR
+#define GIFLIB_MINOR 0
+#endif
+#ifndef GIFLIB_RELEASE
+#define GIFLIB_RELEASE 0
+#endif
+
 /* winuser.h might define DrawText to DrawTextA or DrawTextW.
    Undefine before redefining to avoid a preprocessor warning.  */
 #ifdef DrawText
@@ -7220,17 +7234,6 @@ gif_image_p (Lisp_Object object)
 
 #endif /* HAVE_NTGUI */
 
-/* Giflib before 5.0 didn't define these macros.  */
-#ifndef GIFLIB_MAJOR
-#define GIFLIB_MAJOR 4
-#endif
-#ifndef GIFLIB_MINOR
-#define GIFLIB_MINOR 0
-#endif
-#ifndef GIFLIB_RELEASE
-#define GIFLIB_RELEASE 0
-#endif
-
 #ifdef WINDOWSNT
 
 /* GIF library details.  */
@@ -7269,7 +7272,9 @@ init_gif_functions (void)
 #define fn_DGifSlurp		DGifSlurp
 #define fn_DGifOpen		DGifOpen
 #define fn_DGifOpenFileName	DGifOpenFileName
-#define fn_GifErrorString	GifErrorString
+#if 5 <= GIFLIB_MAJOR
+# define fn_GifErrorString	GifErrorString
+#endif
 
 #endif /* WINDOWSNT */