fixed alternate form for 'x' and 'X' formats

same fix exists in original code:
https://svn.apache.org/viewvc?view=revision&revision=1152309

Author: arnaud-lb

main/spprintf.c

@@ -211,7 +211,7 @@ static void xbuf_format_converter(smart_str *xbuf, const char *fmt, va_list ap)
 
 	double fp_num;
 	wide_int i_num = (wide_int) 0;
-	u_wide_int ui_num;
+	u_wide_int ui_num = (u_wide_int) 0;
 
 	char num_buf[NUM_BUF_SIZE];
 	char char_buf[2];			/* for printing %% and %<unknown> */
@@ -560,7 +560,7 @@ static void xbuf_format_converter(smart_str *xbuf, const char *fmt, va_list ap)
 					s = ap_php_conv_p2(ui_num, 4, *fmt,
 								&num_buf[NUM_BUF_SIZE], &s_len);
 					FIX_PRECISION(adjust_precision, precision, s, s_len);
-					if (alternate_form && i_num != 0) {
+					if (alternate_form && ui_num != 0) {
 						*--s = *fmt;	/* 'x' or 'X' */
 						*--s = '0';
 						s_len += 2;