[Bug fortran/68566] ICE on using unusable array in reshape (double free or corruption)

[gerhard.steinmetz.fortran@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68566

--- Comment #11 from Gerhard Steinmetz <gerhard.steinmetz.fortran@t-online.de> ---
Another constellation (appearing legal) :


$ cat zz1.f90
program p
   integer :: n(2) = [2,1]
   print *, reshape ([1,2,3,4,5,6], [2,4], [0,0], [2,1])
   print *, reshape ([1,2,3,4,5,6], [2,4], [0,0], n)
   print *, reshape ([1,2,3,4,5,6], [2,4], [0,0], [n])
end


$ gfortran-6 zz1.f90
f951: internal compiler error: Segmentation fault


$ gfortran-7-20160626 zz1.f90
f951: internal compiler error: Segmentation fault
0xc0bdff crash_signal
        ../../gcc/toplev.c:335
0x66230e gfc_check_reshape(gfc_expr*, gfc_expr*, gfc_expr*, gfc_expr*)
        ../../gcc/fortran/check.c:3848
0x6949a4 check_specific
        ../../gcc/fortran/intrinsic.c:4274
0x69dd84 gfc_intrinsic_func_interface(gfc_expr*, int)
        ../../gcc/fortran/intrinsic.c:4489
0x6e27c6 resolve_unknown_f
        ../../gcc/fortran/resolve.c:2718
0x6e27c6 resolve_function
        ../../gcc/fortran/resolve.c:3020
0x6e27c6 gfc_resolve_expr(gfc_expr*)
        ../../gcc/fortran/resolve.c:6353
0x6e7241 gfc_resolve_code(gfc_code*, gfc_namespace*)
        ../../gcc/fortran/resolve.c:10446
0x6e6f9b gfc_resolve_blocks(gfc_code*, gfc_namespace*)
        ../../gcc/fortran/resolve.c:9497
0x6e734e gfc_resolve_code(gfc_code*, gfc_namespace*)
        ../../gcc/fortran/resolve.c:10436
0x6e9a22 resolve_codes
        ../../gcc/fortran/resolve.c:15644
0x6e9b11 gfc_resolve(gfc_namespace*)
        ../../gcc/fortran/resolve.c:15678
0x6d4fea resolve_all_program_units
        ../../gcc/fortran/parse.c:5782
0x6d4fea gfc_parse_file()
        ../../gcc/fortran/parse.c:6034
0x717692 gfc_be_parse_file
        ../../gcc/fortran/f95-lang.c:201

# (configured with --enable-checking=yes)


---


$ cat zz2.f90
program p
   integer, allocatable :: n(:)
   n = [2,1]
   print *, reshape ([1,2,3,4,5,6], [2,4], [0,0], [2,1])
   print *, reshape ([1,2,3,4,5,6], [2,4], [0,0], n)
   print *, reshape ([1,2,3,4,5,6], [2,4], [0,0], [n])
end


$ gfortran-6 zz2.f90
*** Error in `/usr/lib64/gcc/x86_64-suse-linux/6/f951': double free or
corruption (fasttop): 0x000000000232c4c0 ***
#...
f951: internal compiler error: Aborted