changes from feedback

Author: devnexen

ext/gmp/gmp.c

@@ -1278,23 +1278,37 @@ ZEND_FUNCTION(gmp_pow)
 
 	if (Z_TYPE_P(base_arg) == IS_LONG && Z_LVAL_P(base_arg) >= 0) {
 		INIT_GMP_RETVAL(gmpnum_result);
-		if ((log10(Z_LVAL_P(base_arg)) * exp) > (double)ULONG_MAX) {
-			zend_value_error("base and exponent overflow");
-			RETURN_THROWS();
+		if (exp > UINT_MAX) {
+			mpz_t base_num, exp_num, mod;
+			mpz_init(base_num);
+			mpz_init(exp_num);
+			mpz_init(mod);
+			mpz_set_si(base_num, Z_LVAL_P(base_arg));
+			mpz_set_si(exp_num, exp);
+			mpz_set_si(mod, UINT_MAX);
+			mpz_powm(gmpnum_result, base_num, exp_num, mod);
+			mpz_clear(mod);
+			mpz_clear(exp_num);
+			mpz_clear(base_num);
+		} else {
+			mpz_ui_pow_ui(gmpnum_result, Z_LVAL_P(base_arg), exp);
 		}
-		mpz_ui_pow_ui(gmpnum_result, Z_LVAL_P(base_arg), exp);
 	} else {
 		mpz_ptr gmpnum_base;
-		unsigned long gmpnum;
 		FETCH_GMP_ZVAL(gmpnum_base, base_arg, temp_base, 1);
 		INIT_GMP_RETVAL(gmpnum_result);
-		gmpnum = mpz_get_ui(gmpnum_base);
-		if ((log10(gmpnum) * exp) > (double)ULONG_MAX) {
-			FREE_GMP_TEMP(temp_base);
-			zend_value_error("base and exponent overflow");
-			RETURN_THROWS();
+		if (exp > UINT_MAX) {
+			mpz_t exp_num, mod;
+			mpz_init(exp_num);
+			mpz_init(mod);
+			mpz_set_si(exp_num, exp);
+			mpz_set_si(mod, UINT_MAX);
+			mpz_powm(gmpnum_result, gmpnum_base, exp_num, mod);
+			mpz_clear(mod);
+			mpz_clear(exp_num);
+		} else {
+			mpz_pow_ui(gmpnum_result, gmpnum_base, exp);
 		}
-		mpz_pow_ui(gmpnum_result, gmpnum_base, exp);
 		FREE_GMP_TEMP(temp_base);
 	}
 }

ext/gmp/tests/gmp_pow_fpe.phpt

@@ -6,17 +6,15 @@ gmp
 <?php
 $g = gmp_init(256);
 
-try {
-	gmp_pow($g, PHP_INT_MAX);
-} catch (\ValueError $e) {
-	echo $e->getMessage() . PHP_EOL;
+var_dump(gmp_pow($g, PHP_INT_MAX));
+var_dump(gmp_pow(256, PHP_INT_MAX));
+?>
+--EXPECTF--
+object(GMP)#2 (1) {
+  ["num"]=>
+  string(%d) "%s"
 }
-try {
-	gmp_pow(256, PHP_INT_MAX);
-} catch (\ValueError $e) {
-	echo $e->getMessage();
+object(GMP)#2 (1) {
+  ["num"]=>
+  string(%d) "%s"
 }
-?>
---EXPECT--
-base and exponent overflow
-base and exponent overflow