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* [Bug c/49933] New: float pointer postincrement during complex calculations increments twice
@ 2011-08-01 13:58 michael.pippig at mathematik dot tu-chemnitz.de
2011-08-01 14:51 ` [Bug c/49933] " rguenth at gcc dot gnu.org
0 siblings, 1 reply; 2+ messages in thread
From: michael.pippig at mathematik dot tu-chemnitz.de @ 2011-08-01 13:58 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49933
Summary: float pointer postincrement during complex
calculations increments twice
Product: gcc
Version: 4.6.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
AssignedTo: unassigned@gcc.gnu.org
ReportedBy: michael.pippig@mathematik.tu-chemnitz.de
Created attachment 24882
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=24882
Multiply complex array with float array. Use pointer postincrement ++ to go
through the float array.
The postincrement operator of float pointers is evaluated twice, if it is used
during complex calculations, e.g., the simple multiplication of the complex
array c and the float array f in the way
# for(k=0;k<N;k++)
# c[k] *= (*f_ptr++);
results in
# for(k=0;k<N;k++)
# c[k] *= f_ptr[2*k];
instead of the expected result
# for(k=0;k<N;k++)
# c[k] *= f_ptr[k];
Ziel: x86_64-unknown-linux-gnu
Konfiguriert mit: ../gcc-4.6.1/configure
--prefix=/lustrefs/compiler/gcc-4.6/gcc-4.6.1
Thread-Modell: posix
gcc-Version 4.6.1 (GCC)
^ permalink raw reply [flat|nested] 2+ messages in thread
* [Bug c/49933] float pointer postincrement during complex calculations increments twice
2011-08-01 13:58 [Bug c/49933] New: float pointer postincrement during complex calculations increments twice michael.pippig at mathematik dot tu-chemnitz.de
@ 2011-08-01 14:51 ` rguenth at gcc dot gnu.org
0 siblings, 0 replies; 2+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-08-01 14:51 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49933
Richard Guenther <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution| |DUPLICATE
--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-08-01 14:50:17 UTC ---
This is a dup of PR49644.
*** This bug has been marked as a duplicate of bug 49644 ***
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2011-08-01 13:58 [Bug c/49933] New: float pointer postincrement during complex calculations increments twice michael.pippig at mathematik dot tu-chemnitz.de
2011-08-01 14:51 ` [Bug c/49933] " rguenth at gcc dot gnu.org
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