g77 bug with ENTRY statement

[Toon Moene]

craig@jcb-sc.com wrote:

> Steven Kargl wrote:

> >      i=int(z)              ! z is no longer in scope.

> Yes it is.  Judicious use of GOTOs would make it perfectly okay for
> code literally following the ENTRY in the source to refer to Z.  It
> is only because the code flows from that Z-less ENTRY into a reference
> to Z that an undefined behavior is triggered.

> > g77 should issue a warning that z is a dummy argument in
> > subroutine a() and that it is undefined at entry b().

> That'd be great.  Ideally the gcc back end would notice this, but the
> way the front end tells it about what's going on basically prevents
> it.

It would indeed be very nice if g77 produced a clear warning here.

Just as a data point:  Both SGI's f90 and f77 version 7.2.1. didn't warn
about this construct when using their -ansi options.

Executables produced by both versions of the compiler dumped core in
exactly (as far as possible) the same manner as that generated by g77.

-- 
Toon Moene (toon@moene.indiv.nluug.nl)
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GNU Fortran: http://world.std.com/~burley/g77.html