RFA: handle zero-length types in value_from_register

[Jim Blandy]

Andrew Cagney <cagney@gnu.org> writes:
> > Andrew Cagney <cagney@gnu.org> writes:
> >
> >> > 2004-01-27  Jim Blandy  <jimb@redhat.com>
> >> > 	* findvar.c (value_from_register): If the type has no length,
> >> > just
> >> > 	return an acceptable value --- don't report an internal error.
> >> >
> >
> >> This looks to need a test case.
> > I tried to put one together, but the bug only occurs when the
> > zero-length value is allocated to a register.  I couldn't find any way
> > to make that happen at all.  So the only known instance of this bug
> > depends on bad debug info.
> 
> The commentary should really reflect this important detail (also
> mention the compiler that's broken for instance).  Should GDB also
> complain about the bogus info?

Seems reasonable.  I've attached a revision of the original patch,
with an expanded comment, and a separate patch that makes GDB complain
when it sees the bogus info.

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