[Bug c++/28879] [4.0/4.1/4.2 regression] ICE with variable-sized array in template function

[Bug c++/28879] [4.0/4.1/4.2 regression] ICE with variable-sized array in template function

[reichelt at gcc dot gnu dot org]

-- 

reichelt at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.0.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] New: [4.0/4.1/4.2 regression] ICE with variable-sized array in template function

[reichelt at gcc dot gnu dot org]

The following valid code snippet triggers an ICE since GCC 3.4.0:

==========================
struct A
{
  int i;
};

template<int> void foo()
{
  int x[A().i];
}
==========================

bug.cc: In function 'void foo()':
bug.cc:8: internal compiler error: in value_dependent_expression_p, at
cp/pt.c:12761
Please submit a full bug report, [etc.]

The following similar code snippet triggers an ICE since GCC 4.0.0:

==========================
struct A
{
  static int i;
};

template<int> void foo()
{
  int x[A::i];
}
==========================

bug.cc: In function 'void foo()':
bug.cc:8: internal compiler error: tree check: did not expect class 'type',
have 'type' (record_type) in contains_placeholder_p, at tree.c:2190
Please submit a full bug report, [etc.]


-- 
           Summary: [4.0/4.1/4.2 regression] ICE with variable-sized array
                    in template function
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code, monitored
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: reichelt at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2 regression] ICE with variable-sized array in template function

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2006-08-28 23:57 -------
(In reply to comment #0)
> The following similar code snippet triggers an ICE since GCC 4.0.0:
That one is related to PR 27210.

Really these are two different bugs and should have been filed seperately.

For that one I bet we should change a save_expr to cp_save_expr which should
solve it.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2 regression] ICE with variable-sized array in template function

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2006-08-29 02:44 -------
Actually the second case is because we call:
426         t = build_array_type (elt_type, index_type);
#12 0x081e0cae in build_cplus_array_type_1 (elt_type=0xb7c62284,
index_type=0xb7d055c0)
    at ../../gcc/cp/tree.c:426


And the first problem was introduced with an ABI change:
6524      if (abi_version_at_least (2)
6525          /* We should only handle value dependent expressions specially. 
*/
6526          ? value_dependent_expression_p (size)
#3  0x08084f4f in compute_array_index_type (name=0xb7cea09c, size=0xb7cba0c8)
    at ../../gcc/cp/decl.c:6524

If you do -fabi-version=1, we get the ICE later on but with the same problem:
417       if (dependent_type_p (elt_type)
418           || (index_type
419               && value_dependent_expression_p (TYPE_MAX_VALUE
(index_type))))
#4  0x081e0c31 in build_cplus_array_type_1 (elt_type=0xb7cf0284,
index_type=0xb7d93564)
    at ../../gcc/cp/tree.c:417


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2006-08-29 02:44:38
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2 regression] ICE with variable-sized array in template function

[mmitchel at gcc dot gnu dot org]

-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2 regression] ICE with VLA in template function

[mmitchel at gcc dot gnu dot org]

-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |mark at codesourcery dot com
                   |dot org                     |
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2/4.3 regression] ICE with VLA in template function

[gdr at gcc dot gnu dot org]

------- Comment #3 from gdr at gcc dot gnu dot org  2007-02-03 19:42 -------
won't fix in GCC-4.0.x.  Adjusting milestone.


-- 

gdr at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.0.4                       |4.1.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2/4.3 regression] ICE with VLA in template function

[pinskia at gcc dot gnu dot org]

-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.1.3                       |4.1.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2/4.3 regression] ICE with VLA in template function

[mmitchel at gcc dot gnu dot org]

-- 

mmitchel at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.1.2                       |4.1.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2/4.3 regression] ICE with VLA in template function

[pinskia at gcc dot gnu dot org]

------- Comment #4 from pinskia at gcc dot gnu dot org  2007-03-07 22:39 -------
*** Bug 31064 has been marked as a duplicate of this bug. ***


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |larsand at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2/4.3 regression] ICE with VLA in template function

[jakub at gcc dot gnu dot org]

------- Comment #5 from jakub at gcc dot gnu dot org  2007-11-19 23:31 -------
http://gcc.gnu.org/ml/gcc-patches/2007-11/msg01014.html
fixes the second testcase.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |http://gcc.gnu.org/ml/gcc-
                   |                            |patches/2007-
                   |                            |11/msg01014.html


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2/4.3 regression] ICE with VLA in template function

[jakub at gcc dot gnu dot org]

------- Comment #6 from jakub at gcc dot gnu dot org  2007-11-20 06:38 -------
Subject: Bug 28879

Author: jakub
Date: Tue Nov 20 06:38:48 2007
New Revision: 130309

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=130309
Log:
        PR c++/28879
        * tree.c (build_cplus_array_type_1): Don't pass any VLA types
        when processing_template_decl to build_array_type.

        * g++.dg/template/vla2.C: New test.

Added:
    trunk/gcc/testsuite/g++.dg/template/vla2.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/tree.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2/4.3 regression] ICE with VLA in template function

[jason at gcc dot gnu dot org]

------- Comment #7 from jason at gcc dot gnu dot org  2008-02-13 18:14 -------
The problem is that value_dependent_expression_p expects to only be called with
constant-expression arguments, but a VLA leads to calling it with a
non-constant expression argument, and we abort when we notice a cast to a
non-arithmetic type, which must not appear in a constant-expression.

Either value_dependent_expression_p needs to handle arbitrary VLA bounds, or we
need to avoid calling it if the array bound is not a constant-expression.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.0/4.1/4.2/4.3 regression] ICE with VLA in template function

[mark at codesourcery dot com]

------- Comment #8 from mark at codesourcery dot com  2008-02-13 18:18 -------
Subject: Re:  [4.0/4.1/4.2/4.3 regression] ICE with VLA in
 template function

jason at gcc dot gnu dot org wrote:

> Either value_dependent_expression_p needs to handle arbitrary VLA bounds, or we
> need to avoid calling it if the array bound is not a constant-expression.

Exactly so.  My intent when writing v_d_e_p was that it only be called 
with constant-expressions.  (The whole idea of value-dependent 
expressions in the standard is predicated on them being 
constant-expressions; the goal is to partition constant-expressions 
which whose value is known before template substitution from those whose 
values is not known until later.)

So, I suggest that we take the second approach.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.2/4.3/4.4 regression] ICE with VLA in template function

[jsm28 at gcc dot gnu dot org]

------- Comment #9 from jsm28 at gcc dot gnu dot org  2008-07-04 21:29 -------
Closing 4.1 branch.


-- 

jsm28 at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[4.1/4.2/4.3/4.4 regression]|[4.2/4.3/4.4 regression] ICE
                   |ICE with VLA in template    |with VLA in template
                   |function                    |function
   Target Milestone|4.1.3                       |4.2.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.2/4.3/4.4 regression] ICE with VLA in template function

[jason at gcc dot gnu dot org]

------- Comment #10 from jason at gcc dot gnu dot org  2009-03-20 19:36 -------
Taking.


-- 

jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|mark at codesourcery dot com|jason at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.2/4.3/4.4 regression] ICE with VLA in template function

[jason at gcc dot gnu dot org]

------- Comment #11 from jason at gcc dot gnu dot org  2009-03-21 20:16 -------
Subject: Bug 28879

Author: jason
Date: Sat Mar 21 20:15:41 2009
New Revision: 144988

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=144988
Log:
        PR c++/28879
        * parser.c (cp_parser_direct_declarator): In a template, wrap
        non-constant expression in NOP_EXPR with TREE_SIDE_EFFECTS set.
        * pt.c (tsubst): Preserve it in a partial instantiation.
        (dependent_type_p_r): Don't check value_dependent_expression_p.
        * decl.c (compute_array_index_type): Don't check
        value_dependent_expression_p if TREE_SIDE_EFFECTS.

Added:
    trunk/gcc/testsuite/g++.dg/ext/vla6.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/decl.c
    trunk/gcc/cp/parser.c
    trunk/gcc/cp/pt.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.2/4.3/4.4 regression] ICE with VLA in template function

[jason at gcc dot gnu dot org]

------- Comment #12 from jason at gcc dot gnu dot org  2009-03-21 20:50 -------
Fixed.


-- 

jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.2/4.3 Regression] ICE with VLA in template function

[rguenth at gcc dot gnu dot org]

------- Comment #13 from rguenth at gcc dot gnu dot org  2009-03-21 21:14 -------
Re-open.  Fixed on the trunk.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
      Known to work|                            |4.4.0
         Resolution|FIXED                       |
            Summary|[4.2/4.3/4.4 regression] ICE|[4.2/4.3 Regression] ICE
                   |with VLA in template        |with VLA in template
                   |function                    |function


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.2/4.3 Regression] ICE with VLA in template function

[jason at gcc dot gnu dot org]

------- Comment #14 from jason at gcc dot gnu dot org  2009-03-22 03:07 -------
I'm not inclined to apply the fix to 4.2/4.3.


-- 

jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|jason at gcc dot gnu dot org|unassigned at gcc dot gnu
                   |                            |dot org
             Status|REOPENED                    |NEW


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.3 Regression] ICE with VLA in template function

[jsm28 at gcc dot gnu dot org]

------- Comment #15 from jsm28 at gcc dot gnu dot org  2009-03-31 19:41 -------
Closing 4.2 branch.


-- 

jsm28 at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[4.2/4.3 Regression] ICE    |[4.3 Regression] ICE with
                   |with VLA in template        |VLA in template function
                   |function                    |
   Target Milestone|4.2.5                       |4.3.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.3 Regression] ICE with VLA in template function

[rguenth at gcc dot gnu dot org]

------- Comment #16 from rguenth at gcc dot gnu dot org  2009-08-04 12:27 -------
GCC 4.3.4 is being released, adjusting target milestone.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.3.4                       |4.3.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879

[Bug c++/28879] [4.3 Regression] ICE with VLA in template function

[rguenth at gcc dot gnu dot org]

------- Comment #17 from rguenth at gcc dot gnu dot org  2010-04-20 13:24 -------
WONTFIX for 4.3 as of comment #14.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
      Known to fail|4.0.4                       |4.0.4 4.3.4
         Resolution|                            |FIXED
   Target Milestone|4.3.5                       |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28879