[Bug bootstrap/36108] [4.4 Regression]: revision 134865 breaks gcc bootstrap

[Bug bootstrap/36108] [4.4 Regression]: revision 134865 breaks gcc bootstrap

[hjl dot tools at gmail dot com]

-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.4.0
            Version|4.3.0                       |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36108

[Bug bootstrap/36108] New: [4.4 Regression]: revision 134865 breaks gcc bootstrap

[hjl dot tools at gmail dot com]

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Revision 134865:

http://gcc.gnu.org/ml/gcc-patches/2008-04/msg01945.html

breaks gcc bootstrap:

cc1: warnings being treated as errors
/export/gnu/src/gcc/gcc/gcc/real.c: In function ‘real_to_integer2’:
/export/gnu/src/gcc/gcc/gcc/real.c:1387: error: array subscript is negative
/export/gnu/src/gcc/gcc/gcc/real.c: In function ‘real_from_integer’:
/export/gnu/src/gcc/gcc/gcc/real.c:2066: error: array subscript is negative
make[5]: *** [real.o] Error 1
make[5]: *** Waiting for unfinished jobs....

The code looks like

      if ((8 * 8) == (8 * 8)) 
 {
   high = t.sig[((128 + (8 * 8)) / (8 * 8))-1];
   low = t.sig[((128 + (8 * 8)) / (8 * 8))-2];
 }
      else  
 {
   ((void)(!((8 * 8) == 2*(8 * 8)) ? fancy_abort
("/export/gnu/src/gcc/gcc/gcc/real.c", 1380, __FUNCTION__), 0 : 0));
   high = t.sig[((128 + (8 * 8)) / (8 * 8))-1];
   high = high << ((8 * 8) - 1) << 1; 
   high |= t.sig[((128 + (8 * 8)) / (8 * 8))-2];

   low = t.sig[((128 + (8 * 8)) / (8 * 8))-3];
   low = low << ((8 * 8) - 1) << 1; 
   low |= t.sig[((128 + (8 * 8)) / (8 * 8))-4];
 }

We have

low |= t.sig[((128 + (8 * 8)) / (8 * 8))-4];

which is

low |= t.sig[-1];

But it never reached.


-- 
           Summary: [4.4 Regression]: revision 134865 breaks gcc bootstrap
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: blocker
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hjl dot tools at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36108

[Bug bootstrap/36108] [4.4 Regression]: revision 134865 breaks gcc bootstrap

[hjl dot tools at gmail dot com]

------- Comment #1 from hjl dot tools at gmail dot com  2008-05-02 12:44 -------
It happens on Linux/Intel64.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36108

[Bug bootstrap/36108] [4.4 Regression]: revision 134865 breaks gcc bootstrap

[hjl dot tools at gmail dot com]

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------- Comment #2 from hjl dot tools at gmail dot com  2008-05-02 12:48 -------
A simple testcase:

bash-3.2$ cat x.c
int foo [10];

int
bar (int i)
{
  if (8 == 8)
    return foo [1];
  else
   return foo [-1];
}
bash-3.2$  ./xgcc -B./ -O2 x.c -c -Wall -Werror
cc1: warnings being treated as errors
x.c: In function ‘bar’:
x.c:9: error: array subscript is negative
bash-3.2$ 


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36108

[Bug bootstrap/36108] [4.4 Regression]: revision 134865 breaks gcc bootstrap

[jv244 at cam dot ac dot uk]

------- Comment #3 from jv244 at cam dot ac dot uk  2008-05-02 14:35 -------
confirmed on x86_64-unknown-linux-gnu


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jv244 at cam dot ac dot uk changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2008-05-02 14:35:43
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36108

[Bug bootstrap/36108] [4.4 Regression]: revision 134865 breaks gcc bootstrap

[pinskia at gcc dot gnu dot org]

------- Comment #4 from pinskia at gcc dot gnu dot org  2008-05-02 16:02 -------
See this is why I did not want this warning in the front-end.


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pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |build, diagnostic


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36108

[Bug bootstrap/36108] [4.4 Regression]: revision 134865 breaks gcc bootstrap

[hjl dot tools at gmail dot com]

------- Comment #5 from hjl dot tools at gmail dot com  2008-05-02 21:35 -------
Fixed by revision 134889.


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hjl dot tools at gmail dot com changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36108