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Re: Someone has caused regressions in gfortran


> Sadly, the testsuite regressions don't seems to be fixed.  I will try to
> figure out tomorrow why the function is still being inlined.

The test case gfortran.dg/do_3.F90 pass with -fno-strict-overflow
(see http://gcc.gnu.org/ml/fortran/2007-09/msg00116.html).
I have posted at http://gcc.gnu.org/ml/fortran/2007-09/msg00107.html
a reduced test case without inlining issues showing a similar
breakage.  If someone can show that before the recent failure
the functions were not inlined, I think the failure would
be fully explained. Otherwise it will require further investigation.

As far as I can tell without -fno-strict-overflow the executable
reduces to a call abort at the level of 

if (i /= final) call abort

as if final = huge(to)+1_1 giving an overflow, the comparison is
assuming to always fail.  I remember a lot of traffic on the gcc mailing
list a couple months ago about this kind of optimization and the
reasons behind -fno-strict-overflow, but I dont have the time right
now to look deeper.

Dominique


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