[Bug fortran/92470] CFI_address wrongly assumes that lower bounds are at zero – invalid for pointers + allocatables

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92470

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2019-11-12
     Ever confirmed|0                           |1

--- Comment #2 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Patch: https://gcc.gnu.org/ml/gcc-patches/2019-11/msg00928.html

 * * *

While fixing it, I run into the question which lower_bound is to be expected
for CFI_section and for CFI_establish, cf.
https://mailman.j3-fortran.org/pipermail/j3/2019-November/thread.html#11740 (PR
89843 also talks about CFI_section.)

The current implementation of CFI_section seems to be fine (according to Bob
and Bill), however, I still think it is not well specified.
Regarding CFI_establish, there is still the question what should be the value
of lower_bound for CFI_attribute_other. (gfortran uses '0' for pointer as
demanded by the standard and '1' otherwise (unspecified).)