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* [Bug c/58016] stdatomic.h missing in 4.8.1
[not found] <bug-58016-4@http.gcc.gnu.org/bugzilla/>
@ 2013-07-28 18:31 ` paolo.carlini at oracle dot com
2013-07-28 19:27 ` joseph at codesourcery dot com
` (6 subsequent siblings)
7 siblings, 0 replies; 8+ messages in thread
From: paolo.carlini at oracle dot com @ 2013-07-28 18:31 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58016
Paolo Carlini <paolo.carlini at oracle dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Severity|blocker |normal
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug c/58016] stdatomic.h missing in 4.8.1
[not found] <bug-58016-4@http.gcc.gnu.org/bugzilla/>
2013-07-28 18:31 ` [Bug c/58016] stdatomic.h missing in 4.8.1 paolo.carlini at oracle dot com
@ 2013-07-28 19:27 ` joseph at codesourcery dot com
2013-07-28 20:42 ` jeff.science at gmail dot com
` (5 subsequent siblings)
7 siblings, 0 replies; 8+ messages in thread
From: joseph at codesourcery dot com @ 2013-07-28 19:27 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58016
--- Comment #1 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
I don't know whether Andrew intends stdatomic.h to go in GCC or glibc, but
in any case I consider this a duplicate of bug 53769, which in turn I
don't really consider a useful bug report at all (incompleteness of the
implementation of an option documented in the manual as incomplete should
not be considered a bug).
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug c/58016] stdatomic.h missing in 4.8.1
[not found] <bug-58016-4@http.gcc.gnu.org/bugzilla/>
2013-07-28 18:31 ` [Bug c/58016] stdatomic.h missing in 4.8.1 paolo.carlini at oracle dot com
2013-07-28 19:27 ` joseph at codesourcery dot com
@ 2013-07-28 20:42 ` jeff.science at gmail dot com
2013-07-29 13:43 ` joseph at codesourcery dot com
` (4 subsequent siblings)
7 siblings, 0 replies; 8+ messages in thread
From: jeff.science at gmail dot com @ 2013-07-28 20:42 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58016
--- Comment #2 from Jeff Hammond <jeff.science at gmail dot com> ---
If GCC doesn't support C11, it should not claim to support C11 via
__STDC_VERSION__. The C11 standard definition isn't a recommendation from
which implementers can pick and choose based upon their priorities.
Documentation an implementations failure to comply with a standard does not
absolve an implementation from lying about its features with ISO standard
macros. The macro is part of the standard; the documentation is not.
In any case, there is an absolutely trivial way for GCC to satisfy the C11
standard with respect to stdatomic.h, and it involves __STDC_NO_ATOMICS__. The
failure to define this macro or to provide stdatomic.h make GCC non-compliant
with C11, in which case __STDC_VERSION__ is defined improperly.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug c/58016] stdatomic.h missing in 4.8.1
[not found] <bug-58016-4@http.gcc.gnu.org/bugzilla/>
` (2 preceding siblings ...)
2013-07-28 20:42 ` jeff.science at gmail dot com
@ 2013-07-29 13:43 ` joseph at codesourcery dot com
2013-07-29 16:15 ` jeff.science at gmail dot com
` (3 subsequent siblings)
7 siblings, 0 replies; 8+ messages in thread
From: joseph at codesourcery dot com @ 2013-07-29 13:43 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58016
--- Comment #4 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
__STDC_VERSION__ describes *intent* of command-line options (as regards
differences between standard versions, to the extent that those are
implemented). This is the same principle that has been documented for
__STDC__ since at least GCC 2.0.
"Sometimes people say that defining @code{__STDC__} in a compiler that
does not completely conform to the ANSI C standard somehow violates the
standard. This is illogical. The standard is a standard for compilers
that are supposed to conform. It says nothing about what any other
compilers should do. Whatever the ANSI C standard says is relevant to
the design of plain @samp{gcc} without @samp{-ansi} only for pragmatic
reasons, not as a requirement."
(quoted from the GCC 2.0 manual).
As a pragmatic matter, it's useful for users of standards modes that are
incomplete to be able to tell which of those modes is in use, and
__STDC_VERSION__ is the natural macro to define to distinguish between
them. gcc -std=c11 is a compiler explicitly claimed not to conform.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug c/58016] stdatomic.h missing in 4.8.1
[not found] <bug-58016-4@http.gcc.gnu.org/bugzilla/>
` (3 preceding siblings ...)
2013-07-29 13:43 ` joseph at codesourcery dot com
@ 2013-07-29 16:15 ` jeff.science at gmail dot com
2013-07-29 16:34 ` jeff.science at gmail dot com
` (2 subsequent siblings)
7 siblings, 0 replies; 8+ messages in thread
From: jeff.science at gmail dot com @ 2013-07-29 16:15 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58016
--- Comment #5 from Jeff Hammond <jeff.science at gmail dot com> ---
Can someone tell me where the appropriate place to define __STDC_NO_ATOMICS__
and __STDC_NO_THREADS__ in GCC so I can submit a patch? I'd rather solve the
problem and take 1-2 steps forward towards C11 compliance rather than debate
the philosophical aspects of the problem.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug c/58016] stdatomic.h missing in 4.8.1
[not found] <bug-58016-4@http.gcc.gnu.org/bugzilla/>
` (4 preceding siblings ...)
2013-07-29 16:15 ` jeff.science at gmail dot com
@ 2013-07-29 16:34 ` jeff.science at gmail dot com
2013-07-29 16:39 ` joseph at codesourcery dot com
2013-07-29 18:46 ` jeff.science at gmail dot com
7 siblings, 0 replies; 8+ messages in thread
From: jeff.science at gmail dot com @ 2013-07-29 16:34 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58016
Jeff Hammond <jeff.science at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jeff.science at gmail dot com
--- Comment #6 from Jeff Hammond <jeff.science at gmail dot com> ---
Created attachment 30568
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30568&action=edit
patch to define macros indicating missing C11 support
If GCC defines __STDC_NO_ATOMICS__ and __STDC_NO_THREADS__, it is no longer
non-compliant w.r.t. C11 to not provide stdatomic.h and threads.h. This would
resolve bugs 53769 and 58016, albeit in a trivial way.
I will not be surprised at all if this patch is rejected, if for no other
reason than my institution has not signed a contributor agreement with FSF
(they almost certainly will if I ask). My goal is to inspire someone else to
do it properly since it seems trivial and arguably necessary.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug c/58016] stdatomic.h missing in 4.8.1
[not found] <bug-58016-4@http.gcc.gnu.org/bugzilla/>
` (5 preceding siblings ...)
2013-07-29 16:34 ` jeff.science at gmail dot com
@ 2013-07-29 16:39 ` joseph at codesourcery dot com
2013-07-29 18:46 ` jeff.science at gmail dot com
7 siblings, 0 replies; 8+ messages in thread
From: joseph at codesourcery dot com @ 2013-07-29 16:39 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58016
--- Comment #7 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
__STDC_NO_THREADS__ is defined in glibc's stdc-predef.h because it
describes combination compiler and library properties.
The correct fix for atomics for 4.9 will be to implement them - see Andrew
MacLeod's patches and recent discussion on gcc-patches - and the state of
C11 in 4.8 is what it is and 4.8 is subject to normal release branch rules
(regression and documentation fixes only, generally).
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug c/58016] stdatomic.h missing in 4.8.1
[not found] <bug-58016-4@http.gcc.gnu.org/bugzilla/>
` (6 preceding siblings ...)
2013-07-29 16:39 ` joseph at codesourcery dot com
@ 2013-07-29 18:46 ` jeff.science at gmail dot com
7 siblings, 0 replies; 8+ messages in thread
From: jeff.science at gmail dot com @ 2013-07-29 18:46 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58016
Jeff Hammond <jeff.science at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution|--- |INVALID
--- Comment #8 from Jeff Hammond <jeff.science at gmail dot com> ---
My patch was w.r.t. the trunk as of earlier today, not 4.8 but that's fine. I
just subscribed to various GCC lists to track these developments.
I'll apply my patch locally so that I can use 4.8.1 and get the desired
behavior.
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2013-07-29 18:46 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
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[not found] <bug-58016-4@http.gcc.gnu.org/bugzilla/>
2013-07-28 18:31 ` [Bug c/58016] stdatomic.h missing in 4.8.1 paolo.carlini at oracle dot com
2013-07-28 19:27 ` joseph at codesourcery dot com
2013-07-28 20:42 ` jeff.science at gmail dot com
2013-07-29 13:43 ` joseph at codesourcery dot com
2013-07-29 16:15 ` jeff.science at gmail dot com
2013-07-29 16:34 ` jeff.science at gmail dot com
2013-07-29 16:39 ` joseph at codesourcery dot com
2013-07-29 18:46 ` jeff.science at gmail dot com
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