https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102011
kargl at gcc dot gnu.org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |kargl at gcc dot gnu.org
Status|UNCONFIRMED |RESOLVED
Resolution|--- |INVALID
--- Comment #1 from kargl at gcc dot gnu.org ---
(In reply to Ralph Trenkler from comment #0)
> Created attachment 51346 [details]
> The fortran program, which does the infinite loop with compiler version
> 10.3.0
>
> I wrote a function in gfortran-10.3.0, which computes the square root with
> the heron iteration method. Without optimization the program is okay, but if
> I turn on optimization, then it does an infinite loop. I use Kubuntu 20.04.
If I compile your program with -Wall, I get
gfcx -o z -fcheck=all -Wall a.f90 && ./z
a.f90:11:13:
11 | if (abs((x2-x1)/(x1+x2)) < epsilon) exit
| ^
Warning: 'epsilon' may be used uninitialized [-Wmaybe-uninitialized]
Sure, enough.
real(8), parameter :: epilson = 1.0e-15
^^^^^^^
if (abs((x2-x1)/(x1+x2)) < epsilon) exit
^^^^^^^
One of these is wrong.
