[Bug fortran/32884] New: ICE: Accessing non-local variable in PURE function

[Bug fortran/32884] New: ICE: Accessing non-local variable in PURE function

[burnus at gcc dot gnu dot org]

Using the following invalid program, one gets an ICE
 NAG f95: Assignment to Z in PURE procedure BAR

gfortran: segmentation fault.

subroutine foo ()
  integer :: z
contains
  pure function bar (a)
    integer, intent(in) :: a
    integer :: bar
    z = 45 ! <<<<<<<<<<<
    bar = a
  end function bar
end subroutine foo


-- 
           Summary: ICE: Accessing non-local variable in PURE function
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Keywords: ice-on-invalid-code
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: burnus at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32884

[Bug fortran/32884] ICE: Accessing non-local variable in PURE function

[burnus at gcc dot gnu dot org]

------- Comment #1 from burnus at gcc dot gnu dot org  2007-07-24 17:33 -------
Seemingly the error is detected and only on writing the error the segmentation
fault occurs:

==494== Invalid read of size 8
==494==    at 0x41D398: show_locus (error.c:171)
==494==    by 0x41D29D: error_print (error.c:521)
==494==    by 0x41DB1E: gfc_error (error.c:759)
==494==    by 0x45B930: resolve_code (resolve.c:5871)
==494==    by 0x45BB10: resolve_codes (resolve.c:8472)
==494==    by 0x45BACF: resolve_codes (resolve.c:8464)
==494==    by 0x45BB54: gfc_resolve (resolve.c:8491)
==494==    by 0x44E507: gfc_parse_file (parse.c:3271)
==494==    by 0x472FBD: gfc_be_parse_file (f95-lang.c:301)
==494==    by 0x6B4BC3: toplev_main (toplev.c:1044)
==494==    by 0x52BEB43: (below main) (in /lib64/libc-2.6.so)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32884

[Bug fortran/32884] ICE: Accessing non-local variable in PURE function

[burnus at gcc dot gnu dot org]

------- Comment #2 from burnus at gcc dot gnu dot org  2007-07-24 18:28 -------
Others cannot reproduce it (on i686 & x86_64), but here I can with gfortran-4.1
& 4.2 of SUSE, with the vanilla 4.2 and with 4.3.

The problem is for whatever reason the "&code->expr->where" argument to
gfc_error(). In error_print the "loc" argument is not NULL, but loc->lb->*
point to invalid locations, which gave an memory access error (segfault) in
show_locus when accessing lb->file.

484                   loc = va_arg (argp, locus *);
486                 if (have_l1)
(gdb) p loc
$8 = (locus *) 0xfdc13a
(gdb) p loc->lb
$9 = (gfc_linebuf *) 0x610072616200736e
(gdb) p loc->lb->file
Cannot access memory at address 0x6100726162007376
(gdb) p loc->lb->line
Cannot access memory at address 0x610072616200738a
(gdb) p loc->lb->file
Cannot access memory at address 0x6100726162007376

But no problem for others.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32884

[Bug fortran/32884] ICE: Accessing non-local variable in PURE function

[burnus at gcc dot gnu dot org]

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------- Comment #3 from burnus at gcc dot gnu dot org  2007-07-24 18:53 -------
This is a translation bug:

msgid "Cannot assign to variable '%s' in PURE procedure at %L"
msgstr "In PURE-Prozedur bei %L kann nicht an Variable »%s« zugewiesen werden"

As %L / %s is reverted, gfortran crashes.

Solution: Replace %L ... %s  by %2$L ... %1$s

I reported the bug to the DE language team.


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32884