[Bug c/16973] New: Differences between addresses of labels broken

[Bug c/16973] New: Differences between addresses of labels broken

[jsm28 at gcc dot gnu dot org]

In the course of writing a formal model of constant expressions,
including the GNU extensions which have been requested, I found
that one of these, differences such as &&a - &&b in initializers,
doesn't actually work properly.  This is a regression from 3.4.x.

void
f (void)
{
  static __SIZE_TYPE__ x = &&a - &&b;
  a : b : return;
}

compiles to a .s file, but with mainline the .s file is invalid:

/home/jsm28/tmp/tmpdir/ccASoFOw.s: Assembler messages:
/home/jsm28/tmp/tmpdir/ccASoFOw.s:7: Error: can't resolve `.text' {.text
section} - `.L2' {*UND* section}

        .file   "t.c"
        .data
        .align 4
        .type   x.1120, @object
        .size   x.1120, 4
x.1120:
        .long   .L1-.L2
        .text
        .align 4
.globl f
        .type   f, @function
f:
        pushl   %ebp
        movl    %esp, %ebp
        popl    %ebp
        ret
.L1:
        .size   f, .-f
        .ident  "GCC: (GNU) 3.5.0 20040810 (experimental)"
        .section        .note.GNU-stack,"",@progbits

(note the absence of a .L2 label).

3.4.1 generates working output with the difference of two
assembler labels that actually exist (although oddly the
labels aren't at the same place).

-- 
           Summary: Differences between addresses of labels broken
           Product: gcc
           Version: 3.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jsm28 at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [3.5 Regression] Differences between addresses of labels broken

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-08-10 21:32 -------
Confirmed, I think this is the same problem which is causing PR 15014 to fail.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
  BugsThisDependsOn|                            |15014
           Severity|normal                      |critical
             Status|UNCONFIRMED                 |NEW
          Component|c                           |middle-end
     Ever Confirmed|                            |1
           Keywords|                            |wrong-code
   Last reconfirmed|0000-00-00 00:00:00         |2004-08-10 21:32:51
               date|                            |
            Summary|Differences between         |[3.5 Regression] Differences
                   |addresses of labels broken  |between addresses of labels
                   |                            |broken
   Target Milestone|---                         |3.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [3.5 Regression] Differences between addresses of labels broken

[reichelt at gcc dot gnu dot org]

------- Additional Comments From reichelt at gcc dot gnu dot org  2004-08-13 09:04 -------
Jan, the trouble started with your patch
  http://gcc.gnu.org/ml/gcc-cvs/2004-06/msg00795.html
Could you please have a look?


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |reichelt at gcc dot gnu dot
                   |                            |org, hubicka at gcc dot gnu
                   |                            |dot org
           Keywords|                            |monitored


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [3.5 Regression] Differences between addresses of labels broken

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-08-13 14:07 -------
try at -O1 which most likely has this problem for longer.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [3.5 Regression] Differences between addresses of labels broken

[reichelt at gcc dot gnu dot org]

------- Additional Comments From reichelt at gcc dot gnu dot org  2004-08-13 14:40 -------
> try at -O1 which most likely has this problem for longer.

Yup, you were right, Andrew.
With -O or higher I get failures since 2004-06-08 whereas 2004-06-06
seems to be fine. This probably corresponds to comment #6 in PR 15014.

Sorry for bothering you, Jan!


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [4.0 Regression] Differences between addresses of labels broken

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-04 14:29 -------
Mine, I have a fix will send it out soon.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |pinskia at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [4.0 Regression] Differences between addresses of labels broken

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-04 14:46 -------
Patch here: <http://gcc.gnu.org/ml/gcc-patches/2004-10/msg00246.html>.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |patch


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [4.0 Regression] Differences between addresses of labels broken

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-07 17:19 -------
Since Jeff says this is the wrong approach I am not going to update my patch because I have better 
things to do with my time than fix cfgcleanup.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|pinskia at gcc dot gnu dot  |unassigned at gcc dot gnu
                   |org                         |dot org
             Status|ASSIGNED                    |NEW


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [4.0 Regression] Differences between addresses of labels broken

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-10 17:54 -------
Patch which fixes the problem and is a better fix than my first patch which does not work all ways:
<http://gcc.gnu.org/ml/gcc-patches/2004-10/msg00860.html>.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |pinskia at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [4.0 Regression] Differences between addresses of labels broken

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-10-18 19:29 -------
Subject: Bug 16973

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	pinskia@gcc.gnu.org	2004-10-18 19:29:53

Modified files:
	gcc            : ChangeLog tree-cfg.c 

Log message:
	2004-10-18  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR middle-end/15014
	PR middle-end/16973
	* tree-cfg.c (remove_bb): If we have a label expression in the
	basic block and the label we have taken the address, move the
	label expression to the basic block which is previous in the
	linked list.
	(tree_verify_flow_info): Fix printing out the label name of the
	problematic label expression.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.5932&r2=2.5933
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/tree-cfg.c.diff?cvsroot=gcc&r1=2.79&r2=2.80



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [4.0 Regression] Differences between addresses of labels broken

[pinskia at gcc dot gnu dot org]

-- 
Bug 16973 depends on bug 15014, which changed state.

Bug 15014 Summary: [4.0 regression] labels after are removed even though they are used
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15014

           What    |Old Value                   |New Value
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [4.0 Regression] Differences between addresses of labels broken

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-10-18 19:38 -------
Subject: Bug 16973

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	pinskia@gcc.gnu.org	2004-10-18 19:38:47

Modified files:
	gcc/testsuite  : ChangeLog 
Added files:
	gcc/testsuite/gcc.dg: pr16973.c 

Log message:
	2004-10-18  Andrew Pinski  <pinskia@physics.uc.edu>
	
	PR middle-end/16973
	* gcc.dg/pr16973.c: New test.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.4469&r2=1.4470
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.dg/pr16973.c.diff?cvsroot=gcc&r1=NONE&r2=1.1



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973

[Bug middle-end/16973] [4.0 Regression] Differences between addresses of labels broken

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-10-18 19:39 -------
Fixed.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16973