Regression with parameter_array_init_3.f90

[Steve Kargl]

On Thu, Jan 10, 2008 at 08:06:01AM +0100, Paul Thomas wrote:
> Steve,
> >Sigh.  I spent too much time on this today :(, except those associated 
> >with endian-ness.  Nothing, nada, ne rien...
> >  
> I bootstrapped and regtested on x86_ia64/FC8, which normally catches all 
> the ailments that are going
> >The segfault is occurring in find_array_element() of expr.c.
> >This function is called 3 times.  The first 2 return because
> >e->expr_type in line 1023 is not constant.  The third trip into
> >this function I get the segfault.  AFAICT, something is
> >messed up with the ar structure.  Unfortunately, I can't
> >use gdb to trace into this function (it appears to be inlined).
> >If I try to set a break point on find_array_element, gdb tells
> >me that symbol does not exist!
> >
> >  
> I noticed that the backtrace that you posted is a bit odd - line numbers 
> and function calls are de-synched.  I am at a complete loss to explain 
> it.  Have you tried clearing your tree to bedrock and rebuilding?  Does 
> anybody else see it?
> 
> Thanks for your efforts.
> 

#0  0x000000020100c810 in __gmpn_add_n () from /usr/local/lib/libgmp.so.7
#1  0x0000000200ff912d in __gmpz_add () from /usr/local/lib/libgmp.so.7
#2  0x0000000000423b62 in simplify_const_ref (p=0x201497900)
    at ../../gcc4x/gcc/fortran/expr.c:1049

If I look at p in gdb I see

(gdb) print *p->ref->u->ar->as->upper[0]
$14 = {expr_type = EXPR_FUNCTION, ts = {type = BT_UNKNOWN, kind = 0, 
    derived = 0x0, cl = 0x0, is_c_interop = 0, is_iso_c = 0, 
    f90_type = BT_UNKNOWN}, rank = 0, shape = 0x0, symtree = 0x201401230, 
  ref = 0x0, where = {nextc = 0x20148a20f "len(HEX1)) =  [(1,i=1,len(HEX1))]", 
    lb = 0x20148a1d0}, inline_noncopying_intrinsic = 0, is_boz = 0, 
  con_by_offset = 0x0, representation = {length = 0, string = 0x0}, value = {
    logical = 20976224, integer = {{_mp_alloc = 20976224, _mp_size = 2, 
        _mp_d = 0x0}}, real = {{_mpfr_prec = 8610910816, _mpfr_sign = 0, 
        _mpfr_exp = 0, _mpfr_d = 0x0}}, complex = {r = {{
          _mpfr_prec = 8610910816, _mpfr_sign = 0, _mpfr_exp = 0, 
          _mpfr_d = 0x0}}, i = {{_mpfr_prec = 0, _mpfr_sign = 0, 
          _mpfr_exp = 0, _mpfr_d = 0x0}}}, op = {operator = 20976224, 
      uop = 0x0, op1 = 0x0, op2 = 0x0}, function = {actual = 0x201401260, 
      name = 0x0, isym = 0x0, esym = 0x0}, character = {length = 20976224, 
      string = 0x0}, constructor = 0x201401260}}

I'd expect to see some sort of gfc_evaluate_now() for
EXPR_FUNCTION.  Intstead, it seems to die while dereferencing
p->ref->u->ar->as->upper[0]->value.integer.

BTW, I've checked gmp and it passes all of its tests.

I'll keep hunting.

-- 
Steve