[Bug c/3325] cast of bit-field to same type gets discarded

[Bug c/3325] cast of bit-field to same type gets discarded

[falk at debian dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325


falk at debian dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ms at siroyan dot com


------- Additional Comments From falk at debian dot org  2003-07-06 22:23 -------
*** Bug 6515 has been marked as a duplicate of this bug. ***

[Bug c/3325] cast of bit-field to same type gets discarded

[falk at debian dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325


falk at debian dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |servatius dot brandt at
                   |                            |fujitsu-siemens dot com


------- Additional Comments From falk at debian dot org  2003-07-06 22:23 -------
*** Bug 6346 has been marked as a duplicate of this bug. ***

[Bug c/3325] cast of bit-field to same type gets discarded

[falk at debian dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325


falk at debian dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |marky at model dot com


------- Additional Comments From falk at debian dot org  2003-07-06 22:25 -------
*** Bug 9620 has been marked as a duplicate of this bug. ***

[Bug c/3325] cast of bit-field to same type gets discarded

[falk at debian dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325


falk at debian dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |schwab at suse dot de


------- Additional Comments From falk at debian dot org  2003-07-06 22:24 -------
*** Bug 7696 has been marked as a duplicate of this bug. ***

[Bug c/3325] cast of bit-field to same type gets discarded

[pinskia at physics dot uc dot edu]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325


pinskia at physics dot uc dot edu changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |NEW

[Bug c/3325] cast of bit-field to same type gets discarded

[neroden at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325


neroden at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |neil at gcc dot gnu dot org


------- Additional Comments From neroden at gcc dot gnu dot org  2003-07-14 03:59 -------
Neil, any hope of getting this one into 3.4?  I don't know why the patch was reverted, so I'm not sure how fundamental the issues were...

[Bug c/3325] cast of bit-field to same type gets discarded

[schwab at suse dot de]

------- Additional Comments From schwab at suse dot de  2004-01-21 14:23 -------
Can this be fixed in 3.4? 

-- 
           What    |Removed                     |Added
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    Attachment #276|application/octet-stream    |text/plain
          mime type|                            |
           What    |Removed                     |Added
----------------------------------------------------------------------------
           What    |Removed                     |Added
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   Last reconfirmed|2003-11-16 00:28:12         |2004-01-21 14:23:52
               date|                            |
   Target Milestone|---                         |3.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325

[Bug c/3325] cast of bit-field to same type gets discarded

[jsm at polyomino dot org dot uk]

------- Additional Comments From jsm at polyomino dot org dot uk  2004-01-21 17:59 -------
Subject: Re:  cast of bit-field to same type gets discarded

On Wed, 21 Jan 2004, schwab at suse dot de wrote:

> Can this be fixed in 3.4? 

I very much doubt a patch for it could fail to be too destabilising for a
release branch; in any case, this isn't a regression.  I attempted a
resurrection of the patch and found it needed changes to expand_expr
<http://gcc.gnu.org/ml/gcc-patches/2003-12/msg00651.html> (though no
experts thereon commented on the proper approach); I didn't get a patch to
expand_expr as far as passing both bootstrap/regression tests and all of
the tests below.  I didn't get as far as looking at the debug info
problems with the original patch (the ABI issues were, however, fixed, by
using the declared type when layout was done and adjusting the type to the
bit-field type later).

Note: I don't suppose the original patch passed all the tests below
either, given the need for middle-end support for the bit-field types.  
But presumably it didn't fail the existing regression tests which showed
up the need for middle-end changes, and subsequent C front end changes may
have caused this issue to show up now.

Note: We should also look again at how bool bit-fields work in the light
of the recent dicussion on the WG14 reflector, though I don't think that
reached a clear consensus.

/* Test that operations on bit-fields yield results reduced to bit-field
   type.  */
/* Origin: Joseph Myers <jsm@polyomino.org.uk> */

extern void exit (int);
extern void abort (void);

struct s {
  unsigned long long u33: 33;
  unsigned long long u40: 40;
  unsigned long long u41: 41;
};

struct s a = { 0x100000, 0x100000, 0x100000 };
struct s b = { 0x100000000ULL, 0x100000000ULL, 0x100000000ULL };
struct s c = { 0x1FFFFFFFFULL, 0, 0 };

int 
main (void)
{
  if (a.u33 * a.u33 != 0 || a.u33 * a.u40 != 0 || a.u40 * a.u33 != 0
      || a.u40 * a.u40 != 0)
    abort ();
  if (a.u33 * a.u41 != 0x10000000000ULL
      || a.u40 * a.u41 != 0x10000000000ULL
      || a.u41 * a.u33 != 0x10000000000ULL
      || a.u41 * a.u40 != 0x10000000000ULL
      || a.u41 * a.u41 != 0x10000000000ULL)
    abort ();
  if (b.u33 + b.u33 != 0)
    abort ();
  if (b.u33 + b.u40 != 0x200000000ULL
      || b.u33 + b.u41 != 0x200000000ULL
      || b.u40 + b.u33 != 0x200000000ULL
      || b.u40 + b.u40 != 0x200000000ULL
      || b.u40 + b.u41 != 0x200000000ULL
      || b.u41 + b.u33 != 0x200000000ULL
      || b.u41 + b.u40 != 0x200000000ULL
      || b.u41 + b.u41 != 0x200000000ULL)
    abort ();
  if (a.u33 - b.u33 != 0x100100000ULL
      || a.u33 - b.u40 != 0xFF00100000ULL
      || a.u33 - b.u41 != 0x1FF00100000ULL
      || a.u40 - b.u33 != 0xFF00100000ULL
      || a.u40 - b.u40 != 0xFF00100000ULL
      || a.u40 - b.u41 != 0x1FF00100000ULL
      || a.u41 - b.u33 != 0x1FF00100000ULL
      || a.u41 - b.u40 != 0x1FF00100000ULL
      || a.u41 - b.u41 != 0x1FF00100000ULL)
    abort ();
  if (++c.u33 != 0 || --c.u40 != 0xFFFFFFFFFFULL || c.u41-- != 0)
    abort ();
  exit (0);
}



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325

[Bug c/3325] cast of bit-field to same type gets discarded

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.4.0                       |3.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325

[Bug c/3325] cast of bit-field to same type gets discarded

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-02-25 17:28 -------
*** Bug 14294 has been marked as a duplicate of this bug. ***

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |nathan at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325

[Bug c/3325] cast of bit-field to same type gets discarded

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|3.5.0                       |---


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325

[Bug c/3325] cast of bit-field to same type gets discarded

[falk at debian dot org]

------- Additional Comments From falk at debian dot org  2004-06-17 20:27 -------
*** Bug 16039 has been marked as a duplicate of this bug. ***

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |chanhduy dot tran at gmail
                   |                            |dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325

[Bug c/3325] cast of bit-field to same type gets discarded

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-07-08 08:44 -------
Subject: Bug 3325

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	jsm28@gcc.gnu.org	2004-07-08 08:44:24

Modified files:
	gcc            : c-common.c c-decl.c c-lang.c expr.c 
	                 langhooks-def.h langhooks.h tree-ssa.c tree.c 
	                 tree.h 
	gcc/objc       : objc-act.c objc-lang.c 
	gcc/testsuite  : ChangeLog 
	gcc/testsuite/gcc.dg: bitfld-2.c 
Added files:
	gcc/testsuite/gcc.c-torture/execute: bitfld-3.c 
Removed files:
	gcc/testsuite/gcc.c-torture/execute: bitfld-1.x 

Log message:
	2004-07-08  Joseph S. Myers  <jsm@polyomino.org.uk>
	Neil Booth  <neil@daikokuya.co.uk>
	
	PR c/2511
	PR c/3325
	* c-decl.c (finish_struct): Ensure bit-fields are given the
	correct type.
	* c-common.c (c_common_signed_or_unsigned_type): For C, require
	the precision to match as well as the mode.
	* expr.c (reduce_to_bit_field_precision): New function.
	(expand_expr_real_1): Reduce expressions of bit-field type to
	proper precision.
	* langhooks.h (reduce_bit_field_operations): New hook.
	* langhooks-def.h (LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS):
	Define.
	* c-lang.c, objc/objc-lang.c
	(LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS): Define.
	* objc/objc-act.c (check_ivars): Convert types to bit-field types
	before checking.
	* tree.c (build_nonstandard_integer_type): New function.
	* tree.h (build_nonstandard_integer_type): New prototype.
	* tree-ssa.c (tree_ssa_useless_type_conversion_1): Don't treat
	conversions between integer and boolean types as useless.
	
	testsuite:
	* gcc.c-torture/execute/bitfld-1.x: Remove.
	* gcc.c-torture/execute/bitfld-3.c: New test.
	* gcc.dg/bitfld-2.c: Remove XFAILs.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/c-common.c.diff?cvsroot=gcc&r1=1.527&r2=1.528
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/c-decl.c.diff?cvsroot=gcc&r1=1.528&r2=1.529
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/c-lang.c.diff?cvsroot=gcc&r1=1.129&r2=1.130
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/expr.c.diff?cvsroot=gcc&r1=1.673&r2=1.674
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/langhooks-def.h.diff?cvsroot=gcc&r1=1.83&r2=1.84
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/langhooks.h.diff?cvsroot=gcc&r1=1.89&r2=1.90
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-ssa.c.diff?cvsroot=gcc&r1=2.19&r2=2.20
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree.c.diff?cvsroot=gcc&r1=1.391&r2=1.392
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree.h.diff?cvsroot=gcc&r1=1.546&r2=1.547
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/objc/objc-act.c.diff?cvsroot=gcc&r1=1.229&r2=1.230
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/objc/objc-lang.c.diff?cvsroot=gcc&r1=1.47&r2=1.48
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.3950&r2=1.3951
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.c-torture/execute/bitfld-3.c.diff?cvsroot=gcc&r1=NONE&r2=1.1
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.c-torture/execute/bitfld-1.x.diff?cvsroot=gcc&r1=1.1&r2=NONE
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.dg/bitfld-2.c.diff?cvsroot=gcc&r1=1.2&r2=1.3



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325

[Bug c/3325] cast of bit-field to same type gets discarded

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-07-08 08:46 -------
Subject: Bug 3325

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	jsm28@gcc.gnu.org	2004-07-08 08:45:55

Modified files:
	gcc            : ChangeLog 

Log message:
	2004-07-08  Joseph S. Myers  <jsm@polyomino.org.uk>
	Neil Booth  <neil@daikokuya.co.uk>
	
	PR c/2511
	PR c/3325
	* c-decl.c (finish_struct): Ensure bit-fields are given the
	correct type.
	* c-common.c (c_common_signed_or_unsigned_type): For C, require
	the precision to match as well as the mode.
	* expr.c (reduce_to_bit_field_precision): New function.
	(expand_expr_real_1): Reduce expressions of bit-field type to
	proper precision.
	* langhooks.h (reduce_bit_field_operations): New hook.
	* langhooks-def.h (LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS):
	Define.
	* c-lang.c, objc/objc-lang.c
	(LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS): Define.
	* objc/objc-act.c (check_ivars): Convert types to bit-field types
	before checking.
	* tree.c (build_nonstandard_integer_type): New function.
	* tree.h (build_nonstandard_integer_type): New prototype.
	* tree-ssa.c (tree_ssa_useless_type_conversion_1): Don't treat
	conversions between integer and boolean types as useless.
	
	testsuite:
	* gcc.c-torture/execute/bitfld-1.x: Remove.
	* gcc.c-torture/execute/bitfld-3.c: New test.
	* gcc.dg/bitfld-2.c: Remove XFAILs.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.4372&r2=2.4373



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325

[Bug c/3325] cast of bit-field to same type gets discarded

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-07-08 08:59 -------
Fixed.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |3.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3325