Review feedback by Saki

Author: edorian

ext/bcmath/bcmath.c

@@ -157,8 +157,9 @@ static zend_always_inline zend_result bcmath_check_scale(zend_long scale, uint32
 
 static zend_result bcmath_check_precision(zend_long precision, uint32_t arg_num)
 {
-	if (ZEND_LONG_EXCEEDS_INT(precision)) {
-		zend_argument_value_error(arg_num, "must be between %d and %d", INT_MIN, INT_MAX);
+	if (ZEND_LONG_INT_OVFL(precision)) {
+		zend_argument_value_error(arg_num, "must be between " ZEND_LONG_FMT " and %d",
+			(zend_long) ZEND_LONG_MIN, INT_MAX);
 		return FAILURE;
 	}
 	return SUCCESS;

ext/bcmath/libbcmath/src/round.c

@@ -67,12 +67,10 @@ size_t bc_round(bc_num num, zend_long precision, zend_enum_RoundingMode mode, bc
 			return 0;
 		}
 
-		/* If precision is -3, it becomes 1000. */
-		if (UNEXPECTED(precision == ZEND_LONG_MIN)) {
-			*result = bc_new_num((size_t) ZEND_LONG_MAX + 2, 0);
-		} else {
-			*result = bc_new_num(-precision + 1, 0);
-		}
+		/* If precision is -3, it becomes 1000. Negate in unsigned space so
+		 * precision == ZEND_LONG_MIN doesn't overflow signed long. */
+		zend_ulong magnitude = -(zend_ulong) precision;
+		*result = bc_new_num((size_t) magnitude + 1, 0);
 		(*result)->n_value[0] = 1;
 		(*result)->n_sign = num->n_sign;
 		return 0;

ext/bcmath/tests/bcround_precision_bounds.phpt

@@ -1,5 +1,5 @@
 --TEST--
-bcround() and BcMath\Number::round() reject out-of-range $precision
+bcround() and BcMath\Number::round() reject $precision above INT_MAX
 --EXTENSIONS--
 bcmath
 --SKIPIF--
@@ -11,16 +11,6 @@ try {
 } catch (\ValueError $e) {
     echo $e->getMessage() . \PHP_EOL;
 }
-try {
-    bcround('12345', -PHP_INT_MAX, RoundingMode::AwayFromZero);
-} catch (\ValueError $e) {
-    echo $e->getMessage() . \PHP_EOL;
-}
-try {
-    bcround('12345', PHP_INT_MIN, RoundingMode::AwayFromZero);
-} catch (\ValueError $e) {
-    echo $e->getMessage() . \PHP_EOL;
-}
 try {
     (new BcMath\Number('1'))->round(PHP_INT_MAX);
 } catch (\ValueError $e) {
@@ -31,10 +21,12 @@ try {
 } catch (\ValueError $e) {
     echo $e->getMessage() . \PHP_EOL;
 }
+
+// Large negative precision is accepted: result is a power of 10.
+echo bcround('1', -5, RoundingMode::AwayFromZero) . \PHP_EOL;
 ?>
 --EXPECTF--
-bcround(): Argument #2 ($precision) must be between %i and %i
-bcround(): Argument #2 ($precision) must be between %i and %i
-bcround(): Argument #2 ($precision) must be between %i and %i
-BcMath\Number::round(): Argument #1 ($precision) must be between %i and %i
-BcMath\Number::round(): Argument #1 ($precision) must be between %i and %i
+bcround(): Argument #2 ($precision) must be between %i and %d
+BcMath\Number::round(): Argument #1 ($precision) must be between %i and %d
+BcMath\Number::round(): Argument #1 ($precision) must be between %i and %d
+100000