[Bug c/21839] New: fs/ext3/ialloc.c error: Statement makes a memory store,...

[Bug c/21839] New: fs/ext3/ialloc.c error: Statement makes a memory store,...

[mclinden at informed dot net]

Linux kernel 2.6.11.11
fs/ext3/ialloc.c: In function 'ext_new_inode':
fs/ext3/ialloc.c:423 error: Statement makes a memory store, but has no 
V_MAY_DEFS nor V_MUST_DEFS
#  VUSE <D.14381_251>;
fs/ext3/ialloc.c:423: internal compiler error: verify_ssa failed.

failed at:

struct inode *ext3_new_inode(handle_t *handle, struct inode * dir, int mode)
{

-- 
           Summary: fs/ext3/ialloc.c error: Statement makes a memory
                    store,...
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: mclinden at informed dot net
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux
  GCC host triplet: i686-pc-linux
GCC target triplet: i686-pc-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] fs/ext3/ialloc.c error: Statement makes a memory store,...

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-05-31 13:44 -------
Please give the needed information that is documented on <http://gcc.gnu.org/bugs.html>?

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pinskia at gcc dot gnu dot
                   |                            |org
          Component|c                           |tree-optimization
           Keywords|                            |ice-on-valid-code
            Version|tree-ssa                    |unknown


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] fs/ext3/ialloc.c error: Statement makes a memory store,...

[mclinden at informed dot net]

------- Additional Comments From mclinden at informed dot net  2005-05-31 14:19 -------
Created an attachment (id=9001)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=9001&action=view)
preprocessed ialloc.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] fs/ext3/ialloc.c error: Statement makes a memory store,...

[mclinden at informed dot net]

------- Additional Comments From mclinden at informed dot net  2005-05-31 14:19 -------
Output of gcc -v

Using built-in specs.
Target: i686-pc-linux-gnu
Configured with: ../gcc-4.1-20050528/configure --prefix=/usr --with-mpfr=/usr --
with-mpfr-dir=/usr/src/otai/mpfr-2.1.1 --with-gmp=/usr --with-gmp-
dir=/usr/src/otai/gmp-4.1.4 --enable-shared --enable-__cxa_atexit --enable-
clocale --enable-multilib=no --enable-threads=posix --libexecdir=/usr/lib --
enable-languages=c,c++
Thread model: posix
gcc version 4.1.0 20050528 (experimental)
 /usr/lib/gcc/i686-pc-linux-gnu/4.1.0/cc1 -E -quiet -v -I/usr/src/linux-
2.6.11.11/include fs/ext3/ialloc.c -mtune=pentiumpro -Wstrict-prototypes -
fWall -fomit-frame-pointers -O2 -fpch-preprocess -o ialloc.i
cc1: error: unrecognized command line option "-fWall"
cc1: error: unrecognized command line option "-fomit-frame-pointers"
ignoring nonexistent directory "/usr/lib/gcc/i686-pc-linux-
gnu/4.1.0/../../../../i686-pc-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/src/linux-2.6.11.11/include
 /usr/local/include
 /usr/lib/gcc/i686-pc-linux-gnu/4.1.0/include
 /usr/include
End of search list.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] [4.1 Regression] fs/ext3/ialloc.c error: Statement makes a memory store,...

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-05-31 14:35 -------
Confirmed, reducing.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|fs/ext3/ialloc.c error:     |[4.1 Regression]
                   |Statement makes a memory    |fs/ext3/ialloc.c error:
                   |store,...                   |Statement makes a memory
                   |                            |store,...
   Target Milestone|---                         |4.1.0
            Version|unknown                     |4.1.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] [4.1 Regression] fs/ext3/ialloc.c error: Statement makes a memory store,...

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-05-31 14:45 -------
Confirmed, reduced testcase:
 typedef struct { } spinlock_t;
typedef struct {
 unsigned sequence;
 spinlock_t lock;
} seqlock_t;
void ext3_new_inode(seqlock_t *rsv_seqlock)
{
 *rsv_seqlock = (seqlock_t) { 0, (spinlock_t) { } };
}

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dnovillo at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2005-05-31 14:45:15
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] [4.1 Regression] fs/ext3/ialloc.c error: Statement makes a memory store,...

[giovannibajo at libero dot it]

------- Additional Comments From giovannibajo at libero dot it  2005-05-31 14:59 -------
Sigh, the infamous empty structure extension...

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] [4.1 Regression] ICE for missing V_DEFS caused by salias with empty structures

[giovannibajo at libero dot it]

------- Additional Comments From giovannibajo at libero dot it  2005-05-31 15:01 -------
Compiles with -O2 -fno-tree-salias. Danny, salias is probably confused by empty 
structures.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dberlin at gcc dot gnu dot
                   |                            |org
            Summary|[4.1 Regression]            |[4.1 Regression] ICE for
                   |fs/ext3/ialloc.c error:     |missing V_DEFS caused by
                   |Statement makes a memory    |salias with empty structures
                   |store,...                   |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] [4.1 Regression] ICE for missing V_DEFS caused by salias with empty structures

[dberlin at gcc dot gnu dot org]

------- Additional Comments From dberlin at gcc dot gnu dot org  2005-05-31 16:37 -------
This is indeed an salias problem.

This was code i had warned Nathan about changing, for fear that something like
this might be exposed.

Nathan, 
  if (!var_can_have_subvars (field))
          push = true;
        else if (!(push_fields_onto_fieldstack
                   (TREE_TYPE (field), fieldstack,
                    offset + bitpos_of_field (field)))
                 && DECL_SIZE (field)
                 && !integer_zerop (DECL_SIZE (field)))
          /* Empty structures may have actual size, like in C++. So
             see if we didn't push any subfields and the size is
             nonzero, push the field onto the stack */
          push = true;


fails because DECL_SIZE (field) is 0.

(gdb) p debug_tree (field)
 <field_decl 0x401bd2f4 lock
    type <record_type 0x401bd144 spinlock_t type_0 BLK
        size <integer_cst 0x40140990 constant invariant 0>
        unit size <integer_cst 0x401401b0 constant invariant 0>
        align 8 symtab 0 alias set -1 context <translation_unit_decl 0x401bd804
D.1247>>
    BLK file /home/dberlin/saliastest.c line 4 size <integer_cst 0x40140990 0>
unit size <integer_cst 0x401401b0 0>
    align 8 offset_align 128 offset <integer_cst 0x401401b0 0>
    bit offset <integer_cst 0x40140408 type <integer_type 0x40148288
bit_size_type> constant invariant 32> context <record_type 0x401bd1b0> arguments
<integer_cst 0x401401b0 0>>


But we still need to push it onto the fieldlist anyway, because we have an
access to that member.





-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |nathan at codesourcery dot
                   |                            |com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] [4.1 Regression] ICE for missing V_DEFS caused by salias with empty structures

[nathan at gcc dot gnu dot org]

------- Additional Comments From nathan at gcc dot gnu dot org  2005-05-31 17:25 -------
Are you sure my changes changed this behaviour? IIRC my changes removed the
funky behaviour of ignoring the first field's offset. (well, that was the intent
anyway)  I don't believe I changed the DECL_SIZE check bit.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] [4.1 Regression] ICE for missing V_DEFS caused by salias with empty structures

[dberlin at dberlin dot org]

------- Additional Comments From dberlin at gcc dot gnu dot org  2005-05-31 17:32 -------
Subject: Re:  [4.1 Regression] ICE for missing
	V_DEFS caused by salias with empty structures

On Tue, 2005-05-31 at 17:25 +0000, nathan at gcc dot gnu dot org wrote:
> ------- Additional Comments From nathan at gcc dot gnu dot org  2005-05-31 17:25 -------
> Are you sure my changes changed this behaviour? IIRC my changes removed the
> funky behaviour of ignoring the first field's offset. (well, that was the intent
> anyway)  I don't believe I changed the DECL_SIZE check bit.
> 
I looked, and it appears you are right.
Sorry bout that.
:)




-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] [4.1 Regression] ICE for missing V_DEFS caused by salias with empty structures

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2005-06-02 02:08 -------
Subject: Bug 21839

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	dberlin@gcc.gnu.org	2005-06-02 02:08:03

Modified files:
	gcc            : ChangeLog gimplify.c 
Added files:
	gcc/testsuite/gcc.c-torture/compile: pr21839.c 

Log message:
	2005-06-01  Daniel Berlin  <dberlin@dberlin.org>
	
	Fix PR tree-optimization/21839
	
	* gimplify.c (zero_sized_field_decl): New function.
	(gimplify_init_ctor_eval): Use it.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.8988&r2=2.8989
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/gimplify.c.diff?cvsroot=gcc&r1=2.131&r2=2.132
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.c-torture/compile/pr21839.c.diff?cvsroot=gcc&r1=NONE&r2=1.1



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839

[Bug tree-optimization/21839] [4.1 Regression] ICE for missing V_DEFS caused by salias with empty structures

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-06-02 18:43 -------
Fixed.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21839