diff options
| -rw-r--r-- | bignum.c | 9 | ||||
| -rw-r--r-- | test/ruby/test_numeric.rb | 4 |
2 files changed, 11 insertions, 2 deletions
@@ -7070,7 +7070,7 @@ int_pow_tmp3(VALUE x, VALUE y, VALUE m, int nega_flg) zn = mn; z = bignew(zn, 1); bary_powm_gmp(BDIGITS(z), zn, BDIGITS(x), xn, BDIGITS(y), yn, BDIGITS(m), mn); - if (nega_flg & BIGNUM_POSITIVE_P(z)) { + if (nega_flg && BIGNUM_POSITIVE_P(z) && !BIGZEROP(z)) { z = rb_big_minus(z, m); } RB_GC_GUARD(x); @@ -7098,7 +7098,7 @@ int_pow_tmp3(VALUE x, VALUE y, VALUE m, int nega_flg) x = rb_int_modulo(x, m); } - if (nega_flg && rb_int_positive_p(tmp)) { + if (nega_flg && rb_int_positive_p(tmp) && !rb_int_zero_p(tmp)) { tmp = rb_int_minus(tmp, m); } return tmp; @@ -7210,6 +7210,11 @@ rb_int_powm(int const argc, VALUE * const argv, VALUE const num) rb_raise(rb_eTypeError, "Integer#pow() 2nd argument not allowed unless all arguments are integers"); } + if (rb_int_zero_p(a) && !rb_int_zero_p(b)) { + /* shortcut; 0**x => 0 except for x == 0 */ + return INT2FIX(0); + } + if (rb_int_negative_p(m)) { m = rb_int_uminus(m); nega_flg = 1; diff --git a/test/ruby/test_numeric.rb b/test/ruby/test_numeric.rb index 3bf93ef20d..35496ac875 100644 --- a/test/ruby/test_numeric.rb +++ b/test/ruby/test_numeric.rb @@ -489,6 +489,10 @@ class TestNumeric < Test::Unit::TestCase assert_equal(0, 0.pow(3, 1)) assert_equal(0, 2.pow(3, 1)) assert_equal(0, -2.pow(3, 1)) + + min, max = RbConfig::LIMITS.values_at("FIXNUM_MIN", "FIXNUM_MAX") + assert_equal(0, 0.pow(2, min)) + assert_equal(0, Integer.sqrt(max+1).pow(2, min)) end end |