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* [Bug c/49617] New: gcc misses uninititialized variables in contained functions
@ 2011-07-03 10:06 pault at gcc dot gnu.org
2011-07-04 9:49 ` [Bug c/49617] " rguenth at gcc dot gnu.org
2023-05-20 4:10 ` [Bug middle-end/49617] " pinskia at gcc dot gnu.org
0 siblings, 2 replies; 3+ messages in thread
From: pault at gcc dot gnu.org @ 2011-07-03 10:06 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49617
Summary: gcc misses uninititialized variables in contained
functions
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
AssignedTo: unassigned@gcc.gnu.org
ReportedBy: pault@gcc.gnu.org
This was reported to the gfortran list by Bill Paxton:
gfortran test_uninit.f -O2 -Wall -o test; ./test
module test_mod
implicit none
contains
subroutine test
integer :: x, y
call t
write(*,*) 'y', y
contains
subroutine t
y = x * 5
end subroutine t
end subroutine test
end module test_mod
program test_uninit
use test_mod
implicit none
call test
end program test_uninit
No warning is given that 'x' is used uninitialized in subroutine 't'.
The uninitialized checking is done in tree-ssa.c and tree-ssa-uninit.c, so this
should be attributed to gcc.
Tobias Burnus produced this (using gcc extension) testcase in C
int
main (void)
{
int y;
int func(void)
{
int x;
/*int z;*/
x = y;
/* x = z;*/
return x;
}
return func();
}
This also fails to report on the state of y, when used in 'func'.
I understand that fixing this will not be straightforward but have submitted it
for the record at least.
Paul
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug c/49617] gcc misses uninititialized variables in contained functions
2011-07-03 10:06 [Bug c/49617] New: gcc misses uninititialized variables in contained functions pault at gcc dot gnu.org
@ 2011-07-04 9:49 ` rguenth at gcc dot gnu.org
2023-05-20 4:10 ` [Bug middle-end/49617] " pinskia at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-07-04 9:49 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49617
Richard Guenther <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |diagnostic
Status|UNCONFIRMED |NEW
Last reconfirmed| |2011.07.04 09:48:32
Ever Confirmed|0 |1
Severity|normal |enhancement
--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-07-04 09:48:32 UTC ---
This is similar to other uninitialized reports in that it requires to track
memory. OTOH it is a lot harder because it is an IPA uninitialized use.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug middle-end/49617] gcc misses uninititialized variables in contained functions
2011-07-03 10:06 [Bug c/49617] New: gcc misses uninititialized variables in contained functions pault at gcc dot gnu.org
2011-07-04 9:49 ` [Bug c/49617] " rguenth at gcc dot gnu.org
@ 2023-05-20 4:10 ` pinskia at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-05-20 4:10 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=49617
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Last reconfirmed|2011-07-04 09:48:32 |2023-5-19
Component|c |middle-end
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Hmm, for the C testcase with GCC 5, we do get a warning:
<source>: In function 'main':
<source>:11:6: warning: 'FRAME.0.y' is used uninitialized in this function
[-Wuninitialized]
x = y;
^
There is no warning in GCC 6+ though.
Plus the diagnostic mentions FRAME.0. which is not in the original source.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2023-05-20 4:10 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2011-07-03 10:06 [Bug c/49617] New: gcc misses uninititialized variables in contained functions pault at gcc dot gnu.org
2011-07-04 9:49 ` [Bug c/49617] " rguenth at gcc dot gnu.org
2023-05-20 4:10 ` [Bug middle-end/49617] " pinskia at gcc dot gnu.org
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