bug#12464: 24.2.50; nt/configure.bat fails to detect giflib-5.0.0

[Kazuhiro Ito <kzhr@d1.dion.ne.jp>]

Because gif_lib.h of giflib-5.0.0 assumes size_t is defined (I don't
know whether that is intended), nt/configure.bat fails to check its
availability.

In nt/config.log
> In file included from junk.c:1:0:
> f:/build/emacs-w32/include/gif_lib.h:262:37: error: expected ';', ',' or ')' before 'GifExtensionLength'
> f:/build/emacs-w32/include/gif_lib.h:265:8: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'EGifGCBToExtension'
> The failed program was: 
> #include "gif_lib.h" 
> main (){} 
> gcc -If:/build/emacs-w32/include -If:/build/emacs-w32/include/libxml2 -g  -c junk.c -o junk.obj 
> gcc -If:/build/emacs-w32/include -If:/build/emacs-w32/include/libxml2 -g  -c junk.c -o junk.obj 

Though I don't know whether Emacs supports giflib-5.0.0, the below
patch can fix the problem.  Gif support on my binaries (built by gcc
4.5.2, MinGW) has no problem with giflib-5.0.0 as far as I tested.

=== modified file 'nt/configure.bat'
--- nt/configure.bat	2012-09-08 11:20:32 +0000
+++ nt/configure.bat	2012-09-18 03:14:43 +0000
@@ -627,7 +627,8 @@
 if (%gifsupport%) == (N) goto gifDone
 
 echo Checking for libgif...
-echo #include "gif_lib.h" >junk.c
+echo #include "stdio.h" >junk.c
+echo #include "gif_lib.h" >>junk.c
 echo main (){} >>junk.c
 rem   -o option is ignored with cl, but allows result to be consistent.
 echo %COMPILER% %usercflags% %mingwflag% -c junk.c -o junk.obj >>config.log


-- 
Kazuhiro Ito