fixup! Silence GCC's "cast of pointer to integer of a different size" warning

compat/regex/regcomp.c

@@ -18,6 +18,8 @@
    Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301 USA.  */
 
+#include <stdint.h>
+
 static reg_errcode_t re_compile_internal (regex_t *preg, const char * pattern,
 					  size_t length, reg_syntax_t syntax);
 static void re_compile_fastmap_iter (regex_t *bufp,