[Bug math/13268] New: modf, modff, modfl: help GCC with argument checking

[Bug math/13268] New: modf, modff, modfl: help GCC with argument checking

[bruno at clisp dot org]

http://sourceware.org/bugzilla/show_bug.cgi?id=13268

             Bug #: 13268
           Summary: modf, modff, modfl: help GCC with argument checking
           Product: glibc
           Version: 2.11
            Status: NEW
          Severity: normal
          Priority: P2
         Component: math
        AssignedTo: aj@suse.de
        ReportedBy: bruno@clisp.org
    Classification: Unclassified


The second argument of the functions modf, modff, modfl must not be a NULL
pointer, according to POSIX, and the glibc implementation also does not allow
a NULL pointer.

It would be useful to allow GCC to give a warning when someone passes a NULL
literal to these functions.

How to reproduce:
==================== foo.c ========================
#include <math.h>
#include <stddef.h>
int
main ()
{
  return ! modf (2.4, NULL);
}
===================================================
$ gcc -Wall foo.c

Expected result:
foo.c: In function 'main':
foo.c:6:3: warning: null argument where non-null required (argument 2)

Actual result:
No diagnostic.

The fix should be easy: Add a properly conditionalized
__attribute__ ((__nonnull__ (2)))
to glibc/math/bits/mathcalls.h line 116.

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[Bug math/13268] modf, modff, modfl: help GCC with argument checking

[aj at suse dot de]

http://sourceware.org/bugzilla/show_bug.cgi?id=13268

Andreas Jaeger <aj at suse dot de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED

--- Comment #1 from Andreas Jaeger <aj at suse dot de> 2011-10-12 12:36:01 UTC ---
Thanks. I send a patch to libc-alpha for this.

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[Bug math/13268] modf, modff, modfl: help GCC with argument checking

[drepper.fsp at gmail dot com]

http://sourceware.org/bugzilla/show_bug.cgi?id=13268

Ulrich Drepper <drepper.fsp at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
                 CC|                            |drepper.fsp at gmail dot
                   |                            |com
         Resolution|                            |FIXED

--- Comment #2 from Ulrich Drepper <drepper.fsp at gmail dot com> 2011-10-15 14:09:07 UTC ---
Changed in git.

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[Bug math/13268] modf, modff, modfl: help GCC with argument checking

[fweimer at redhat dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=13268

Florian Weimer <fweimer at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
              Flags|                            |security-

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