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* [Bug c/60858] New: 64-bit multi-character constants
@ 2014-04-16 8:25 swissp2013 at gmail dot com
2014-04-16 8:32 ` [Bug c/60858] " pinskia at gcc dot gnu.org
2014-07-25 19:20 ` [Bug preprocessor/60858] " 3dw4rd at verizon dot net
0 siblings, 2 replies; 3+ messages in thread
From: swissp2013 at gmail dot com @ 2014-04-16 8:25 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60858
Bug ID: 60858
Summary: 64-bit multi-character constants
Product: gcc
Version: 4.10.0
Status: UNCONFIRMED
Severity: enhancement
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: swissp2013 at gmail dot com
Hello All,
There are several real-life cases for 64-bit multi-character constants (ie:
hash tables) that are better handled by the pre-processor (before machine code
generation).
It is trivial for GCC users to resolve the 'per-implementation' behavior
(big-endian vs ...) but they need 64-bit support in the first place.
Currently, a macro has been used to concatenate 32-bit values but this is
adding unecessary bloat in people's C source code.
The GCC 'enhancement' is trivial to make:
---------------------------------------------------------
in gcc-4.9-20140406/libcpp/charset.c:
line 1482:
- size_t max_chars = CPP_OPTION (pfile, int_precision) / width;
+ size_t max_chars = (CHAR_BIT * sizeof (long long int)) / width;
line 1529:
- width = CPP_OPTION(pfile, int_precision);
- width = (CHAR_BIT * sizeof (long long int)) / width;
---------------------------------------------------------
This change won't break existing code - and the warnings will remain - so there
is only a benefit for greybeards like us.
Thank you for your consideration.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug c/60858] 64-bit multi-character constants
2014-04-16 8:25 [Bug c/60858] New: 64-bit multi-character constants swissp2013 at gmail dot com
@ 2014-04-16 8:32 ` pinskia at gcc dot gnu.org
2014-07-25 19:20 ` [Bug preprocessor/60858] " 3dw4rd at verizon dot net
1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2014-04-16 8:32 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60858
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Doing A('a', 'b', 'c', 'd', 'e', 'f', 'g', 'h'); is not that bloated and works
independent of the endian.
Also patches go to gcc-patches@ and should include a testcase or two.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug preprocessor/60858] 64-bit multi-character constants
2014-04-16 8:25 [Bug c/60858] New: 64-bit multi-character constants swissp2013 at gmail dot com
2014-04-16 8:32 ` [Bug c/60858] " pinskia at gcc dot gnu.org
@ 2014-07-25 19:20 ` 3dw4rd at verizon dot net
1 sibling, 0 replies; 3+ messages in thread
From: 3dw4rd at verizon dot net @ 2014-07-25 19:20 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60858
Ed Smith-Rowland <3dw4rd at verizon dot net> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |3dw4rd at verizon dot net
--- Comment #3 from Ed Smith-Rowland <3dw4rd at verizon dot net> ---
You send a message containing a patch (which should include a test case) an
explanation for the change (explanation of method if needed,
motivation/rationale for addition) and a ChangeLog entry to
gcc-patches@gcc.gnu.org. You'll need Copyright paperwork too.
Basically, see https://gcc.gnu.org/contribute.html.
Having said that, at least C++ has standard language specifying 'int' for
multi-character char constants. So I think you'll need to enable this with a
flag, -flong-long-multicharacter-const, maybe.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2014-07-25 19:20 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2014-04-16 8:25 [Bug c/60858] New: 64-bit multi-character constants swissp2013 at gmail dot com
2014-04-16 8:32 ` [Bug c/60858] " pinskia at gcc dot gnu.org
2014-07-25 19:20 ` [Bug preprocessor/60858] " 3dw4rd at verizon dot net
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