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* [Bug c/64609] New: No -Wbool-compare warning on "(a = 0 && 0) <= 4"
@ 2015-01-15 6:58 chengniansun at gmail dot com
2015-01-15 7:24 ` [Bug c/64609] " pinskia at gcc dot gnu.org
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: chengniansun at gmail dot com @ 2015-01-15 6:58 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64609
Bug ID: 64609
Summary: No -Wbool-compare warning on "(a = 0 && 0) <= 4"
Product: gcc
Version: 5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: chengniansun at gmail dot com
This might not be a bug, but a feature request. There is no -Wbool-compare
warning for the following code.
$: cat s.c
int a;
void fn1() { ((a = 0 && 0) <= 4); }
$:
$: gcc-trunk -c s.c -Wbool-compare
$:
$: clang-trunk -c s.c -Wno-unused-value
s.c:2:28: warning: comparison of constant 4 with boolean expression is always
true [-Wtautological-constant-out-of-range-compare]
void fn1() { ((a = 0 && 0) <= 4); }
~~~~~~~~~~~~ ^ ~
1 warning generated.
$:
$:
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/64609] No -Wbool-compare warning on "(a = 0 && 0) <= 4"
2015-01-15 6:58 [Bug c/64609] New: No -Wbool-compare warning on "(a = 0 && 0) <= 4" chengniansun at gmail dot com
@ 2015-01-15 7:24 ` pinskia at gcc dot gnu.org
2015-01-21 8:10 ` [Bug c/64609] No -Wbool-compare warning on "(a = 0 && 0) <= 4" and "0 > a < 0" chengniansun at gmail dot com
2015-03-17 6:55 ` mpolacek at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2015-01-15 7:24 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64609
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Blocks| |49706
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note C the resulting type of a comparison is an integer and not a bool so this
might be causing part of the issue.
This is related to bug 49706 (which I think added -Wbool-compare, I can't keep
track of my own bugs :)).
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/64609] No -Wbool-compare warning on "(a = 0 && 0) <= 4" and "0 > a < 0"
2015-01-15 6:58 [Bug c/64609] New: No -Wbool-compare warning on "(a = 0 && 0) <= 4" chengniansun at gmail dot com
2015-01-15 7:24 ` [Bug c/64609] " pinskia at gcc dot gnu.org
@ 2015-01-21 8:10 ` chengniansun at gmail dot com
2015-03-17 6:55 ` mpolacek at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: chengniansun at gmail dot com @ 2015-01-21 8:10 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64609
Chengnian Sun <chengniansun at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|No -Wbool-compare warning |No -Wbool-compare warning
|on "(a = 0 && 0) <= 4" |on "(a = 0 && 0) <= 4" and
| |"0 > a < 0"
--- Comment #2 from Chengnian Sun <chengniansun at gmail dot com> ---
Another test case.
$: cat s.c
int a;
void f() {
(0 > a < 0);
}
$:
$: gcc-trunk -Wbool-compare -Wtype-limits -c s.c
$:
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/64609] No -Wbool-compare warning on "(a = 0 && 0) <= 4" and "0 > a < 0"
2015-01-15 6:58 [Bug c/64609] New: No -Wbool-compare warning on "(a = 0 && 0) <= 4" chengniansun at gmail dot com
2015-01-15 7:24 ` [Bug c/64609] " pinskia at gcc dot gnu.org
2015-01-21 8:10 ` [Bug c/64609] No -Wbool-compare warning on "(a = 0 && 0) <= 4" and "0 > a < 0" chengniansun at gmail dot com
@ 2015-03-17 6:55 ` mpolacek at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: mpolacek at gcc dot gnu.org @ 2015-03-17 6:55 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64609
Marek Polacek <mpolacek at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2015-03-17
CC| |mpolacek at gcc dot gnu.org
Ever confirmed|0 |1
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2015-03-17 6:55 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-01-15 6:58 [Bug c/64609] New: No -Wbool-compare warning on "(a = 0 && 0) <= 4" chengniansun at gmail dot com
2015-01-15 7:24 ` [Bug c/64609] " pinskia at gcc dot gnu.org
2015-01-21 8:10 ` [Bug c/64609] No -Wbool-compare warning on "(a = 0 && 0) <= 4" and "0 > a < 0" chengniansun at gmail dot com
2015-03-17 6:55 ` mpolacek at gcc dot gnu.org
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