[Bug c++/14545] [3.4/3.5 Regression] Cannot compile pooma-gcc (regression)

["giovannibajo at libero dot it" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From giovannibajo at libero dot it  2004-03-18 01:12 -------
Subject: Re:  [3.4/3.5 Regression] Cannot compile pooma-gcc (regression)

mark at codesourcery dot com wrote:

>> Patch posted, waiting for review:
>> http://gcc.gnu.org/ml/gcc-patches/2004-03/msg01265.html
>>

> Indeed, I think you should just check "!type_dependent_expression_p
> (type) && !INTEGRAL_OR_ENUMERATION_TYPE_P (type)".  I can't remember
> if  that's *quite* right; it might be that casts to floating-point types
> should also be allowed.  You'll have to check the standard for that.
> Would you mind trying that approach please?

This patch implements your suggestion. I checked the standard and you are
right, only casts to integral or enumeration types are allowed in integral
constant expressions. The patch was tested on i686-pc-linux-gnu with no new
regressions, OK for 3.4 and mainline?

Giovanni Bajo



2004-03-16  Giovanni Bajo  <giovannibajo@gcc.gnu.org>

        PR c++/14545
        * parser.c (cp_parser_functional_cast): A cast to anything
        but integral or enumaration type is not an integral constant
        expression.


2004-03-16  Giovanni Bajo  <giovannibajo@gcc.gnu.org>

        PR c++/14545
        * g++.dg/parse/template15.C: New test.



Index: parser.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cp/parser.c,v
retrieving revision 1.183
diff -c -3 -p -r1.183 parser.c
*** parser.c 16 Mar 2004 22:17:59 -0000 1.183
--- parser.c 18 Mar 2004 01:04:57 -0000
*************** static tree
*** 14477,14488 ****
  cp_parser_functional_cast (cp_parser* parser, tree type)
  {
    tree expression_list;

    expression_list
      = cp_parser_parenthesized_expression_list (parser, false,
              /*non_constant_p=*/NULL);

!   return build_functional_cast (type, expression_list);
  }

  /* Save the tokens that make up the body of a member function defined
--- 14477,14499 ----
  cp_parser_functional_cast (cp_parser* parser, tree type)
  {
    tree expression_list;
+   tree cast;

    expression_list
      = cp_parser_parenthesized_expression_list (parser, false,
              /*non_constant_p=*/NULL);

!   cast = build_functional_cast (type, expression_list);
!   /* [expr.const]/1: In an integral constant expression "only type
!      conversions to integral or enumeration type can be used".  */
!   if (cast != error_mark_node && !type_dependent_expression_p (type)
!       && !INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (type)))
!     {
!       if (cp_parser_non_integral_constant_expression
!    (parser, "a call to a constructor"))
!  return error_mark_node;
!     }
!   return cast;
  }

  /* Save the tokens that make up the body of a member function defined



// { dg-do compile }
// Contributed by: Peter Schmid
//   <schmid at snake dot iap dot physik dot tu-darmstadt dot de>
// PR c++/14545: constructor calls are not integer constant expressions

struct A1 { A1(); };
struct A2 { };

template <class T>
struct B
{
  void foo() {
    A1();
    A1 a1 = A1();

    A2();
    A2 a2 = A2();
  }
};

template struct B<void>;




-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14545