[Bug debug/25562] New: [4.1/4.2 Regression] cannot debug VLA local

[Bug debug/25562] New: [4.1/4.2 Regression] cannot debug VLA local

[pinskia at gcc dot gnu dot org]

Take the following code:
int main(void)
{
  int i = 7;
  int t[i];
  int j;
  for(j=0;j<i;j++)
    t[j] = j*j;
}
---

gcc -g t.c
gdb a.out
b t.c:8
run
p t
----
You get:
dwarf expression stack underflow


With 4.0.x, you get:
$1 = 0x7fffff9238a0
Which is okay but not fully there (but that is not a regression).


-- 
           Summary: [4.1/4.2 Regression] cannot debug VLA local
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Keywords: wrong-debug
          Severity: normal
          Priority: P3
         Component: debug
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org
GCC target triplet: x86_64-linux-gnu, i686-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25562

[Bug debug/25562] [4.1/4.2 Regression] cannot debug VLA local

[pinskia at gcc dot gnu dot org]

-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.1.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25562

[Bug debug/25562] [4.1/4.2 Regression] cannot debug VLA local

[jakub at gcc dot gnu dot org]

------- Comment #1 from jakub at gcc dot gnu dot org  2005-12-28 10:23 -------
While GCC 4.0.x had:
        .uleb128 0x3    # (DIE (0x8a) DW_TAG_variable)
        .ascii "t\0"    # DW_AT_name
        .byte   0x1     # DW_AT_decl_file
        .byte   0x5     # DW_AT_decl_line
        .long   0xab    # DW_AT_type
        .byte   0x3     # DW_AT_location
        .byte   0x91    # DW_OP_fbreg
        .sleb128 -32
        .byte   0x6     # DW_OP_deref
4.1 has:
        .uleb128 0x3    # (DIE (0x87) DW_TAG_variable)
        .ascii "t\0"    # DW_AT_name
        .byte   0x1     # DW_AT_decl_file
        .byte   0x5     # DW_AT_decl_line
        .long   0xa6    # DW_AT_type
        .byte   0x1     # DW_AT_location
        .byte   0x6     # DW_OP_deref
but DW_OP_deref needs an argument, but nothing has been pushed on the stack.


-- 

jakub 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         |2005-12-28 10:23:48
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25562

[Bug debug/25562] [4.1/4.2 Regression] cannot debug VLA local

[jakub at gcc dot gnu dot org]

-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jakub at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2005-12-28 10:23:48         |2005-12-28 11:17:59
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25562

[Bug debug/25562] [4.1/4.2 Regression] cannot debug VLA local

[jakub at gcc dot gnu dot org]

------- Comment #2 from jakub at gcc dot gnu dot org  2006-01-04 08:05 -------
Subject: Bug 25562

Author: jakub
Date: Wed Jan  4 08:05:29 2006
New Revision: 109315

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=109315
Log:
        PR debug/25562
        * function.c (instantiate_expr): New function.
        (instantiate_decls_1, instantiate_decls): If DECL_HAS_VALUE_EXPR_P,
        walk its DECL_VALUE_EXPR with instantiate_expr.

        * dwarf2out.c (loc_descriptor_from_tree_1): Don't add
        DW_OP_deref{,_size} if address isn't going to be added.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/dwarf2out.c
    trunk/gcc/function.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25562

[Bug debug/25562] [4.1/4.2 Regression] cannot debug VLA local

[jakub at gcc dot gnu dot org]

------- Comment #3 from jakub at gcc dot gnu dot org  2006-01-04 09:14 -------
Subject: Bug 25562

Author: jakub
Date: Wed Jan  4 09:13:56 2006
New Revision: 109319

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=109319
Log:
        PR debug/25562
        * function.c (instantiate_expr): New function.
        (instantiate_decls_1, instantiate_decls): If DECL_HAS_VALUE_EXPR_P,
        walk its DECL_VALUE_EXPR with instantiate_expr.

        * dwarf2out.c (loc_descriptor_from_tree_1): Don't add
        DW_OP_deref{,_size} if address isn't going to be added.

Modified:
    branches/gcc-4_1-branch/gcc/ChangeLog
    branches/gcc-4_1-branch/gcc/dwarf2out.c
    branches/gcc-4_1-branch/gcc/function.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25562

[Bug debug/25562] [4.1/4.2 Regression] cannot debug VLA local

[jakub at gcc dot gnu dot org]

------- Comment #4 from jakub at gcc dot gnu dot org  2006-01-04 12:33 -------
Fixed.


-- 

jakub at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25562