[Bug fortran/98342] Allocatable component in call to assumed-rank routine causes invalid pointer

[pault at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98342

Paul Thomas <pault at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pault at gcc dot gnu.org
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2020-12-17
           Assignee|unassigned at gcc dot gnu.org      |pault at gcc dot gnu.org

--- Comment #2 from Paul Thomas <pault at gcc dot gnu.org> ---
Googling on munmap_chunk(): invalid pointer reveals that this is quite a
frequent problem.

It originates from the call

out = sel_rank(get_tuple(x))

rather than what happens in either function. Somewhere a free is bein done on
memory that is not malloc'ed.

Bizarrely,

out = sel_rank([get_tuple(x)])

as does

z = get_tuple(x) ! z appropriately declared of course!
out = sel_rank(z)

valgrind confirms this:
....snip....
==535157== Invalid free() / delete / delete[] / realloc()
==535157==    at 0x483A9F5: free (vg_replace_malloc.c:538)
==535157==    by 0x40343A: MAIN__ (pr98342.f90:48)
==535157==    by 0x4035BA: main (pr98342.f90:40)
==535157==  Address 0x1ffeffede0 is on thread 1's stack
==535157==  in frame #1, created by MAIN__ (pr98342.f90:39)
==535157== 
....snip....

The problem arises somewhere in trans-expr.c(gfc_conv_procedure_call).

I am on to it :-)

Paul