bugGNU Common Lisp - Bugs: bug #20992, GCL parses double float incorrectly


bug #20992: GCL parses double float incorrectly

Submitted by:  Robert Dodier <robert_dodier>
Submitted on:  Fri 07 Sep 2007 01:46:42 AM UTC  
Category:  None Severity:  3 - Normal
Item Group:  None Status:  Fixed
Privacy:  Public Assigned to:  None
Open/Closed:  Closed

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Thu 21 Nov 2013 05:01:11 PM UTC, comment #2:

Thanks for your report! Fixed in latest release, 2.6.10.

Camm Maguire <camm>
Project Administrator
Tue 01 Oct 2013 03:31:03 AM UTC, comment #1:

Not observed in GCL 2.6.9 ANSI on Linux.

For the record, features =>


Robert Dodier <robert_dodier>
Fri 07 Sep 2007 01:46:42 AM UTC, original submission:

GCL parses 4.6e8 incorrectly as the same as 4.6 * 1e8, when it should be the same as 46e7. 46e7 is an integer which can be represented exactly as a double float.

Without looking at the GCL source code, I'm guessing that 4.6e8 is parsed by parsing 4.6 and then parsing the exponent separately.

Some similar examples are parsed correctly, and some aren't.

(eql 4.5e8 45e7)
=> T (OK)

(eql 4.9e8 49e7)

Observed in GCL 2.6.7 on Windows and Linux. It might also be present in 2.6.8 on Windows, not sure about that.

There is some discussion about this in Maxima bug report # 1787111.

Robert Dodier <robert_dodier>


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    Follow 2 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2013-11-21 camm StatusNone => Fixed
        Open/ClosedOpen => Closed

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