From: "Joseph S. Myers" <joseph@codesourcery.com>
To: Joern Rennecke <amylaar@spamcop.net>
Cc: Gerald Pfeifer <gerald@pfeifer.com>,
"Paulo J. Matos" <pocmatos@gmail.com>,
gcc@gcc.gnu.org
Subject: Re: C99 Status - inttypes.h
Date: Sun, 25 Sep 2011 22:49:00 -0000 [thread overview]
Message-ID: <Pine.LNX.4.64.1109251621210.8140@digraph.polyomino.org.uk> (raw)
In-Reply-To: <20110925081955.3x5kvx7rc4o88kc8-nzlynne@webmail.spamcop.net>
On Sun, 25 Sep 2011, Joern Rennecke wrote:
> ! <p>"Library Issue" means that support may or may not be available depending
> ! on the C library used; for example, the GNU C library supports all C99
> ! features, provided _ISOC99_SOURCE and/or _GNU_SOURCE is defined in the
> ! source code or with a -D preprocessor flag.
Referring to these feature test macros is not a good idea, the normal way
for them to be defined is internally by libc in response to
__STDC_VERSION__ defined by the compiler.
(There are various miscellaneous conformance issues in glibc as well.
Apart from what's mentioned in libc's CONFORMANCE file:
* Macros that should be usable in #if defined as enums.
* <math.h> and <complex.h> do not declare long double functions when same
representation as double (fixed in EGLIBC by a patch of Jakub's that was
ignored for FSF glibc).
* Mathematical function error handling generally a mess: GLIBC bugs
3866 3868 5680 6759 6776-6788 6792-6799 6801-6810 6814 (this list of bug
numbers may be out of date).
* Mathematical functions broken in non-default rounding modes: GLIBC
bugs 3976 6869.
* Headers redirect functions to standard versions in some cases where C
requires this to work without explicitly including headers (might be
fixable with pragma redefine_extname in implicitly included header).
* wmemcmp/wcscmp handling of some wchar_t values (see recent libc-alpha
discussion; clearly a C94 and C1X conformance bug, less clearly a C99
bug).
* Power Architecture malloc alignment
<http://sourceware.org/ml/libc-alpha/2007-11/msg00062.html> (see more
recent discussion of this patch in the x32 context).
* Fixes to fenv.h fallback functions were rejected 2011-01-08.
* ARM, MIPS wrongly save/restore fp state in setjmp/longjmp.
I'd welcome details of any other issues people think are C standards
conformance bugs in glibc. (I also have some notes of possible issues in
the soft-fp code and architecture-specific issues in some mathematical
functions.))
--
Joseph S. Myers
joseph@codesourcery.com
next prev parent reply other threads:[~2011-09-25 16:36 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-21 14:30 Diogo Sousa
2011-07-21 15:52 ` Joseph S. Myers
2011-07-21 18:13 ` Joe Buck
2011-07-22 11:05 ` Diogo Sousa
2011-07-22 13:03 ` Paulo J. Matos
2011-07-22 15:38 ` Joern Rennecke
2011-07-22 17:43 ` Paulo J. Matos
2011-07-22 20:12 ` James Dennett
2011-07-23 19:29 ` Weddington, Eric
2011-07-23 21:10 ` Eric Botcazou
2011-07-23 22:47 ` Weddington, Eric
2011-08-21 19:27 ` Gerald Pfeifer
2011-09-25 13:00 ` Joern Rennecke
2011-09-25 22:49 ` Joseph S. Myers [this message]
2011-09-25 22:53 ` Gerald Pfeifer
2011-09-26 7:11 ` Joseph S. Myers
2011-07-21 16:06 ` Basile Starynkevitch
2011-07-21 22:45 ` Ian Lance Taylor
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