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* [Bug fortran/98883] New: Module variable not initialized with -finit-real
@ 2021-01-29 11:14 jellby at yahoo dot com
2021-01-29 11:29 ` [Bug fortran/98883] " dominiq at lps dot ens.fr
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: jellby at yahoo dot com @ 2021-01-29 11:14 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98883
Bug ID: 98883
Summary: Module variable not initialized with -finit-real
Product: gcc
Version: 7.5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: jellby at yahoo dot com
Target Milestone: ---
I use -finit-real=nan hoping to catch some uninitialized variables, but
apparently variables in a module are not obeying this flag and are initialized
to something else (zero?):
!=================================
module foo
implicit none
real :: bar
end module foo
program test
use foo
implicit none
real :: w
write(6,*) w
w = bar
write(6,*) w
end program test
!=================================
$ gfortran -finit-real=nan a.f90 && ./a.out
NaN
0.00000000
So, the first printout shows the unitialized w, correctly set to NaN. The
second printout should be the variable in the module, which is zero for some
reason.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug fortran/98883] Module variable not initialized with -finit-real
2021-01-29 11:14 [Bug fortran/98883] New: Module variable not initialized with -finit-real jellby at yahoo dot com
@ 2021-01-29 11:29 ` dominiq at lps dot ens.fr
2021-01-29 18:55 ` kargl at gcc dot gnu.org
2021-01-29 19:04 ` sgk at troutmask dot apl.washington.edu
2 siblings, 0 replies; 4+ messages in thread
From: dominiq at lps dot ens.fr @ 2021-01-29 11:29 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98883
Dominique d'Humieres <dominiq at lps dot ens.fr> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Status|UNCONFIRMED |NEW
Severity|normal |enhancement
Last reconfirmed| |2021-01-29
Priority|P3 |P4
--- Comment #1 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
Confirmed.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug fortran/98883] Module variable not initialized with -finit-real
2021-01-29 11:14 [Bug fortran/98883] New: Module variable not initialized with -finit-real jellby at yahoo dot com
2021-01-29 11:29 ` [Bug fortran/98883] " dominiq at lps dot ens.fr
@ 2021-01-29 18:55 ` kargl at gcc dot gnu.org
2021-01-29 19:04 ` sgk at troutmask dot apl.washington.edu
2 siblings, 0 replies; 4+ messages in thread
From: kargl at gcc dot gnu.org @ 2021-01-29 18:55 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98883
kargl at gcc dot gnu.org changed:
What |Removed |Added
----------------------------------------------------------------------------
Priority|P4 |P5
CC| |kargl at gcc dot gnu.org
--- Comment #2 from kargl at gcc dot gnu.org ---
This bug report should be closed.
Please read the description of option that you are using.
-freal-init=nan applies to **** LOCAL ***** variables.
'bar' is not local to program test, and clearly the option
does not affect variables made available via USE association.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug fortran/98883] Module variable not initialized with -finit-real
2021-01-29 11:14 [Bug fortran/98883] New: Module variable not initialized with -finit-real jellby at yahoo dot com
2021-01-29 11:29 ` [Bug fortran/98883] " dominiq at lps dot ens.fr
2021-01-29 18:55 ` kargl at gcc dot gnu.org
@ 2021-01-29 19:04 ` sgk at troutmask dot apl.washington.edu
2 siblings, 0 replies; 4+ messages in thread
From: sgk at troutmask dot apl.washington.edu @ 2021-01-29 19:04 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98883
--- Comment #3 from Steve Kargl <sgk at troutmask dot apl.washington.edu> ---
On Fri, Jan 29, 2021 at 06:55:16PM +0000, kargl at gcc dot gnu.org wrote:
>
> --- Comment #2 from kargl at gcc dot gnu.org ---
> This bug report should be closed.
>
> Please read the description of option that you are using.
>
> -freal-init=nan applies to **** LOCAL ***** variables.
> 'bar' is not local to program test, and clearly the option
> does not affect variables made available via USE association.
>
I'll also point out that 'bar' is local module
to the module, but as it is unused gfortran
won't initialize it via -finit-real=nan. If you
actual use it, it gets initialized.
module foo
implicit none
real :: bar
contains
subroutine bah
real boo
boo = bar ! <-- Sufficient to get bar = NaN
print *, boo
end subroutine bah
end module foo
program test
use foo
implicit none
real w
print *, w
w = bar
print *, w
end program test
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-01-29 19:04 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2021-01-29 11:14 [Bug fortran/98883] New: Module variable not initialized with -finit-real jellby at yahoo dot com
2021-01-29 11:29 ` [Bug fortran/98883] " dominiq at lps dot ens.fr
2021-01-29 18:55 ` kargl at gcc dot gnu.org
2021-01-29 19:04 ` sgk at troutmask dot apl.washington.edu
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