https://bugs.gentoo.org/898818
https://gitlab.gnome.org/GNOME/libgsf/-/merge_requests/13

From 167d7f96c81683392933ddb8c427e5d7c8ce284d Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Thu, 27 Apr 2023 20:34:34 +0200
Subject: [PATCH] configure.ac: Avoid implicit int in libbz2 probe

Otherwise, this probe will always fail with future compilers,
which are likely not to support implict ints by default.
--- a/configure.ac
+++ b/configure.ac
@@ -427,7 +427,7 @@ if test "x$test_bz2" = xtrue ; then
 	  #undef VERSION
 	  #undef HAVE_STDLIB_H
 	  #include <bzlib.h>
-          main ()
+          int main (void)
           {
             return BZ2_bzDecompressInit (NULL, 0, 0);
           }
-- 
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