Autodetect libgif so extension and try to load it.
diff --git a/configure b/configure
index 9255a4d..c70f226 100755
--- a/configure
+++ b/configure
@@ -15546,6 +15546,80 @@
#define SONAME_LIBUNGIF "$ac_cv_lib_soname_ungif"
_ACEOF
fi
+
+echo "$as_me:$LINENO: checking for -lgif soname" >&5
+echo $ECHO_N "checking for -lgif soname... $ECHO_C" >&6
+if test "${ac_cv_lib_soname_gif+set}" = set; then
+ echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+ ac_get_soname_save_LIBS=$LIBS
+LIBS="-lgif $LIBS"
+ cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h. */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h. */
+
+/* Override any gcc2 internal prototype to avoid an error. */
+#ifdef __cplusplus
+extern "C"
+#endif
+/* We use char because int might match the return type of a gcc2
+ builtin and then its argument prototype would still apply. */
+char DGifOpen ();
+int
+main ()
+{
+DGifOpen ();
+ ;
+ return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
+ (eval $ac_link) 2>conftest.er1
+ ac_status=$?
+ grep -v '^ *+' conftest.er1 >conftest.err
+ rm -f conftest.er1
+ cat conftest.err >&5
+ echo "$as_me:$LINENO: \$? = $ac_status" >&5
+ (exit $ac_status); } &&
+ { ac_try='test -z "$ac_c_werror_flag" || test ! -s conftest.err'
+ { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+ (eval $ac_try) 2>&5
+ ac_status=$?
+ echo "$as_me:$LINENO: \$? = $ac_status" >&5
+ (exit $ac_status); }; } &&
+ { ac_try='test -s conftest$ac_exeext'
+ { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+ (eval $ac_try) 2>&5
+ ac_status=$?
+ echo "$as_me:$LINENO: \$? = $ac_status" >&5
+ (exit $ac_status); }; }; then
+ ac_cv_lib_soname_gif=`$ac_cv_path_LDD conftest$ac_exeext | grep libgif\\.$LIBEXT | sed "s/^.*\(libgif\.$LIBEXT[^ ]*\).*$/\1/"`
+ if test "x$ac_cv_lib_soname_gif" = "x"
+ then
+ ac_cv_lib_soname_gif="libgif.$LIBEXT"
+ fi
+else
+ echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+ac_cv_lib_soname_gif="libgif.$LIBEXT"
+fi
+rm -f conftest.err conftest.$ac_objext \
+ conftest$ac_exeext conftest.$ac_ext
+ LIBS=$ac_get_soname_save_LIBS
+fi
+echo "$as_me:$LINENO: result: $ac_cv_lib_soname_gif" >&5
+echo "${ECHO_T}$ac_cv_lib_soname_gif" >&6
+if test "x$ac_cv_lib_soname_gif" != xNONE
+then
+cat >>confdefs.h <<_ACEOF
+#define SONAME_LIBGIF "$ac_cv_lib_soname_gif"
+_ACEOF
+fi
fi
