[MinGW-notify] [ mingw-Bugs-2997007 ] ANSI mode printf("%a", ...) is incorrect

[SF/projects/mingw n. l. <min...@li...>]

Bugs item #2997007, was opened at 2010-05-05 02:07
Message generated for change (Comment added) made by gustavh
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Category: mingw runtime
Group: None
>Status: Open
Resolution: Fixed
Priority: 5
Private: No
Submitted By: Gustav Hållberg (gustavh)
Assigned to: Keith Marshall (keithmarshall)
Summary: ANSI mode printf("%a", ...) is incorrect

Initial Comment:
printf("%a", ...) produces incorrect output for some numbers.

In particular, it seems to be broken for numbers smaller than the smallest normalized single-precision floating-point number.

I originally saw this using MinGW runtime 3.15.2 and 3.18.0 has the same problem.

Build the test case using gcc -Wall -std=c99 printf-a-bug.c.
When run, it will print:
  0x1p-125 2.35099e-038
  0x0p-126 1.17549e-038
where the second line _should_ read 0x1p-126 (or equivalent).


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>Comment By: Gustav Hållberg (gustavh)
Date: 2012-03-07 10:10

Message:
Sounds good :)

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Comment By: Keith Marshall (keithmarshall)
Date: 2012-03-07 06:26

Message:
Is this still an issue?  I believe it has been fixed; with my current
libmingwex.a build I see:

  $ mingw32-gcc -std=c99 ~/downloads/printf-a-bug.c 
  $ ./a.exe
  0x8p-128 2.35099e-038
  0x8p-129 1.17549e-038

Okay to close?

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You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=102435&aid=2997007&group_id=2435