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* [Bug libstdc++/58850] New: Conversion error in chrono
@ 2013-10-23 1:30 galens at capaccess dot org
2013-10-23 10:07 ` [Bug libstdc++/58850] " paolo.carlini at oracle dot com
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: galens at capaccess dot org @ 2013-10-23 1:30 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58850
Bug ID: 58850
Summary: Conversion error in chrono
Product: gcc
Version: 4.9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: galens at capaccess dot org
Created attachment 31077
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=31077&action=edit
minimal_test_case.cpp
I noticed an odd error when using chrono::duration_cast<> to cast a home-made
Years object (typedef of chrono::duration<long long,std::ratio<36*24*36525,1>>)
to chrono::minutes and chrono::seconds
the conversion to seconds works fine; however, when converting this value into
minutes, I found a (presumably overflow) error.
I've attached a small .cpp that creates a Years object of 12067, and converts
it to seconds and minutes. The following is the output I get:
(and yes, I know that a year isn't actually 365.25 days; the rounding is fine
for my purposes)
<output>
Years: 12067
seconds: 380805559200
Minutes * 60: 123107521440
Minutes: 2051792024
Seconds / 60: 6346759320
</output>
Platform:
Fedora 19 3.11.2 x86_64
GCC 3.9.0 ( locally built, but the only difference from a normal build was
"../configure --enable-languages=c++" )
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug libstdc++/58850] Conversion error in chrono
2013-10-23 1:30 [Bug libstdc++/58850] New: Conversion error in chrono galens at capaccess dot org
@ 2013-10-23 10:07 ` paolo.carlini at oracle dot com
2013-10-23 10:24 ` paolo.carlini at oracle dot com
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: paolo.carlini at oracle dot com @ 2013-10-23 10:07 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58850
Paolo Carlini <paolo.carlini at oracle dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC|galens at capaccess dot org |
--- Comment #1 from Paolo Carlini <paolo.carlini at oracle dot com> ---
The issue boils down to how minutes and hours are defined in our current code:
/// minutes
typedef duration<int, ratio< 60>> minutes;
/// hours
typedef duration<int, ratio<3600>> hours;
See? This, on Linux for sure, *is* conforming because the letter of C++11 says
at least 29 bits and at least 23 bits for those types, does *not* say, eg, 64.
Still I wonder if we couldn't just use int64_t for all the typedefs and be done
with it?!?
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug libstdc++/58850] Conversion error in chrono
2013-10-23 1:30 [Bug libstdc++/58850] New: Conversion error in chrono galens at capaccess dot org
2013-10-23 10:07 ` [Bug libstdc++/58850] " paolo.carlini at oracle dot com
@ 2013-10-23 10:24 ` paolo.carlini at oracle dot com
2013-10-23 13:34 ` paolo.carlini at oracle dot com
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: paolo.carlini at oracle dot com @ 2013-10-23 10:24 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58850
--- Comment #2 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Jon, shall we change this?
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug libstdc++/58850] Conversion error in chrono
2013-10-23 1:30 [Bug libstdc++/58850] New: Conversion error in chrono galens at capaccess dot org
2013-10-23 10:07 ` [Bug libstdc++/58850] " paolo.carlini at oracle dot com
2013-10-23 10:24 ` paolo.carlini at oracle dot com
@ 2013-10-23 13:34 ` paolo.carlini at oracle dot com
2013-10-23 15:31 ` paolo at gcc dot gnu.org
2013-10-23 15:32 ` paolo.carlini at oracle dot com
4 siblings, 0 replies; 6+ messages in thread
From: paolo.carlini at oracle dot com @ 2013-10-23 13:34 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58850
Paolo Carlini <paolo.carlini at oracle dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |ASSIGNED
Last reconfirmed| |2013-10-23
Assignee|unassigned at gcc dot gnu.org |paolo.carlini at oracle dot com
Target Milestone|--- |4.9.0
Ever confirmed|0 |1
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug libstdc++/58850] Conversion error in chrono
2013-10-23 1:30 [Bug libstdc++/58850] New: Conversion error in chrono galens at capaccess dot org
` (2 preceding siblings ...)
2013-10-23 13:34 ` paolo.carlini at oracle dot com
@ 2013-10-23 15:31 ` paolo at gcc dot gnu.org
2013-10-23 15:32 ` paolo.carlini at oracle dot com
4 siblings, 0 replies; 6+ messages in thread
From: paolo at gcc dot gnu.org @ 2013-10-23 15:31 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58850
--- Comment #3 from paolo at gcc dot gnu.org <paolo at gcc dot gnu.org> ---
Author: paolo
Date: Wed Oct 23 15:31:26 2013
New Revision: 203978
URL: http://gcc.gnu.org/viewcvs?rev=203978&root=gcc&view=rev
Log:
2013-10-23 Paolo Carlini <paolo.carlini@oracle.com>
PR libstdc++/58850
* include/std/chrono (minutes, hours): Change typedefs to uniformly
use int64_t.
* testsuite/20_util/duration/arithmetic/58850.cc: New.
Added:
trunk/libstdc++-v3/testsuite/20_util/duration/arithmetic/58850.cc
Modified:
trunk/libstdc++-v3/ChangeLog
trunk/libstdc++-v3/include/std/chrono
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug libstdc++/58850] Conversion error in chrono
2013-10-23 1:30 [Bug libstdc++/58850] New: Conversion error in chrono galens at capaccess dot org
` (3 preceding siblings ...)
2013-10-23 15:31 ` paolo at gcc dot gnu.org
@ 2013-10-23 15:32 ` paolo.carlini at oracle dot com
4 siblings, 0 replies; 6+ messages in thread
From: paolo.carlini at oracle dot com @ 2013-10-23 15:32 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58850
Paolo Carlini <paolo.carlini at oracle dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution|--- |FIXED
--- Comment #4 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Done.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-10-23 15:32 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2013-10-23 1:30 [Bug libstdc++/58850] New: Conversion error in chrono galens at capaccess dot org
2013-10-23 10:07 ` [Bug libstdc++/58850] " paolo.carlini at oracle dot com
2013-10-23 10:24 ` paolo.carlini at oracle dot com
2013-10-23 13:34 ` paolo.carlini at oracle dot com
2013-10-23 15:31 ` paolo at gcc dot gnu.org
2013-10-23 15:32 ` paolo.carlini at oracle dot com
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