Avoid more UB in round()

Author: nikic

Zend/zend_strtod.c

@@ -2705,7 +2705,7 @@ zend_strtod
 				L = c - '0';
 				s1 = s;
 				while((c = *++s) >= '0' && c <= '9')
-					L = 10*L + c - '0';
+					L = 10*L + (c - '0');
 				if (s - s1 > 8 || L > 19999)
 					/* Avoid confusion from exponents
 					 * so large that e might overflow.

ext/standard/math.c

@@ -141,7 +141,7 @@ PHPAPI double _php_math_round(double value, int places, int mode) {
 	/* If the decimal precision guaranteed by FP arithmetic is higher than
 	   the requested places BUT is small enough to make sure a non-zero value
 	   is returned, pre-round the result to the precision */
-	if (precision_places > places && precision_places - places < 15) {
+	if (precision_places > places && precision_places - 15 < places) {
 		int64_t use_precision = precision_places < INT_MIN+1 ? INT_MIN+1 : precision_places;
 
 		f2 = php_intpow10(abs((int)use_precision));