[Bug rtl-optimization/25677] New: [4.2 regression] testsuite failure:gcc.c-torture/execute/960802-1.c -O1 and -O2

[hp at gcc dot gnu dot org]

Last known to work with: "Mon Dec 12 22:04:54 UTC 2005 (revision 108426M)".
Known to fail with: "Mon Jan  2 13:08:54 UTC 2006 (revision 109236M)":

Running
/home/hp/combined/combined/gcc/testsuite/gcc.c-torture/execute/execute.exp ...
FAIL: gcc.c-torture/execute/960802-1.c execution,  -O1
FAIL: gcc.c-torture/execute/960802-1.c execution,  -O2

With the message in gcc.log showing an abort call.
The assembly code acts as if the line
 v = (v & 0x00ffffff) | (o & 0xff000000);
was
 v = o;
(actually there are no instructions which is the same as passing on the
return value from the previous call as the first parameter in this ABI.)
Looking at the RTL dumps, it seems combine is at fault; all the bit fiddling
is gone.
As there has been changes in this area after Jan 2, I expect it to have been
fixed but it seemed proper to add this PR before updating.
I assign it to myself until I've checked whether it remains, so no-one is
tempted to do a wild goose chase.


-- 
           Summary: [4.2 regression] testsuite failure:gcc.c-
                    torture/execute/960802-1.c -O1 and -O2
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: rtl-optimization
        AssignedTo: hp at gcc dot gnu dot org
        ReportedBy: hp at gcc dot gnu dot org
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: cris-axis-elf, cris-axis-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25677