Clojure

Incorrect long quot result involving Long/MIN_VALUE

Details

  • Type: Defect Defect
  • Status: Open Open
  • Priority: Minor Minor
  • Resolution: Unresolved
  • Affects Version/s: Release 1.5
  • Fix Version/s: None
  • Component/s: None
  • Labels:
  • Patch:
    Code and Test
  • Approval:
    Triaged

Description

user=> (quot Long/MIN_VALUE -1)
-9223372036854775808

Similar issue to CLJ-1222 and CLJ-1253, with the same root cause as described for CLJ-1225. Ticket filed separately from CLJ-1253 for long division / because the desired fix may be quite different in this case.

Rich Hickey stated in a comment on CLJ-1225 that this case should throw an exception.

Question: For inc (which throws when given input Long/MAX_VALUE) there is an auto-promoting inc' and an unchecked-inc. quot now throws an exception in this case. Should there be an auto-promoting quot' and an unchecked-quot?

Activity

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Alex Miller added a comment -

quot should throw an an exception on overflow
quot' (I assume not divide' ?) should be added to autopromote on overflow
unchecked-divide should be added to do what quot does now - see CLJ-1545

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Alex Miller added a comment - quot should throw an an exception on overflow quot' (I assume not divide' ?) should be added to autopromote on overflow unchecked-divide should be added to do what quot does now - see CLJ-1545
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Andy Fingerhut added a comment -

Patch clj-1254-2.diff is identical to clj-1254-v1.txt except it applies cleanly to latest master. The only changes were in the context of the lines that were changed, due to a recent commit made.

Show
Andy Fingerhut added a comment - Patch clj-1254-2.diff is identical to clj-1254-v1.txt except it applies cleanly to latest master. The only changes were in the context of the lines that were changed, due to a recent commit made.
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Andy Fingerhut added a comment -

Patch clj-1254-v1.txt causes (quot Long/MIN_VALUE -1) to throw an exception due to overflow of the result, if the arguments are both long.

Unlike inc, which has auto-promoting version inc' and unchecked version unchecked-inc, there is no auto-promoting quot' and unchecked unchecked-quot. This patch does not add one.

Should quot' and unchecked-quot be added? If so, this ticket or a separate one?

Show
Andy Fingerhut added a comment - Patch clj-1254-v1.txt causes (quot Long/MIN_VALUE -1) to throw an exception due to overflow of the result, if the arguments are both long. Unlike inc, which has auto-promoting version inc' and unchecked version unchecked-inc, there is no auto-promoting quot' and unchecked unchecked-quot. This patch does not add one. Should quot' and unchecked-quot be added? If so, this ticket or a separate one?

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Dates

  • Created:
    Updated: