https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83611
Bug ID: 83611
Summary: [PDT] Assignment of parameterized types causes double
free error in runtime
Product: gcc
Version: 8.0
Status: UNCONFIRMED
Keywords: ice-on-valid-code
Severity: normal
Priority: P3
Component: fortran
Assignee: pault at gcc dot gnu.org
Reporter: pault at gcc dot gnu.org
CC: berke.durak at gmail dot com
Blocks: 82173
Target Milestone: ---
Noticed when working on PR83567.
! { dg-do run }
!
module pdt_m
implicit none
type :: vec(k)
integer, len :: k=3
integer :: foo(k)=[1,2,3]
end type vec
end module pdt_m
program test_pdt
use pdt_m
implicit none
type(vec) :: u,v
v = u
end program test_pdt
[pault@pc30 pr83567]$ ~/irun/bin/gfortran -static-libgfortran test.f90
-fdump-tree-original -g
[pault@pc30 pr83567]$ ./a.out
*** Error in `./a.out': double free or corruption (fasttop): 0x00000000007225d0
***
======= Backtrace: =========
/lib64/libc.so.6(+0x77de5)[0x7f5f72fccde5]
....snip....
The tree-dump:
test_pdt ()
{
void * restrict D.3781;
void * restrict D.3782;
static struct Pdtvec u;
static struct Pdtvec v;
try
{
u.k = 3;
u.foo.dim[0].lbound = 1;
u.foo.dim[0].ubound = 3;
u.foo.dim[0].stride = 1;
u.foo.offset = -1;
D.3782 = (void * restrict) __builtin_malloc (12);
u.foo.data = D.3782;
u.foo.dtype = 265;
v.k = 3;
v.foo.dim[0].lbound = 1;
v.foo.dim[0].ubound = 3;
v.foo.dim[0].stride = 1;
v.foo.offset = -1;
D.3781 = (void * restrict) __builtin_malloc (12);
v.foo.data = D.3781;
v.foo.dtype = 265;
v = u; <<<<<<deep copy of PDTs needed
}
finally
{
if ((integer(kind=4)[0:] * restrict) v.foo.data != 0B)
{
__builtin_free ((void *) v.foo.data);
}
v.foo.data = 0B;
if ((integer(kind=4)[0:] * restrict) u.foo.data != 0B)
{
__builtin_free ((void *) u.foo.data);
}
u.foo.data = 0B;
}
}
__attribute__((externally_visible))
main (integer(kind=4) argc, character(kind=1) * * argv)
{
static integer(kind=4) options.0[7] = {68, 8191, 0, 1, 1, 0, 31};
_gfortran_set_args (argc, argv);
_gfortran_set_options (7, &options.0[0]);
test_pdt ();
return 0;
}
Note the lack of default initialization too :-(
Some work is needed to copy PDTs and to ensure the initialization.
I'm on to it.
Paul
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82173
[Bug 82173] [meta-bug] Parameterized derived type errors
