Bug #21814: 0.pow(2,-9999999999999999990) should be zero

• Status: Closed
• Assignee: -
• Target version: 4.0
• ruby -v: 4.1dev
• Backport: 3.2: REQUIRED, 3.3: REQUIRED, 3.4: DONE, 4.0: DONE

[matz (Yukihiro Matsumoto)]

When I try 0.pow(2,-9999999999999999990), irb prints -9999999999999999990, but I think no matter what you divide zero by, the modulo should be zero.

Matz.

[nobu (Nobuyoshi Nakada)]

• Backport changed from 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN to 3.2: REQUIRED, 3.3: REQUIRED, 3.4: REQUIRED, 4.0: REQUIRED

[nobu (Nobuyoshi Nakada)]

GH-15771

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed

Applied in changeset git|19e539c9ee1701b34189fa0c1feb942adeb0e326.

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[Bug #21814] Fix negative bignum modulo

If modulo is zero, do not apply bias even if the divisor is zero.
BIGNUM_POSITIVE_P is true even on bignum zero.

[k0kubun (Takashi Kokubun)]

• Backport changed from 3.2: REQUIRED, 3.3: REQUIRED, 3.4: REQUIRED, 4.0: REQUIRED to 3.2: REQUIRED, 3.3: REQUIRED, 3.4: REQUIRED, 4.0: DONE

ruby_4_0 893dcb5f25cbb0574ae73aa8fc926fd26750a27f merged revision(s) 19e539c9ee1701b34189fa0c1feb942adeb0e326.

[nagachika (Tomoyuki Chikanaga)]

• Backport changed from 3.2: REQUIRED, 3.3: REQUIRED, 3.4: REQUIRED, 4.0: DONE to 3.2: REQUIRED, 3.3: REQUIRED, 3.4: DONE, 4.0: DONE

ruby_3_4 8fa17ea3b2c857369c808a4384ff7ff8174d69f8 merged revision(s) 19e539c9ee1701b34189fa0c1feb942adeb0e326.