[Bug other/54814] New: [4.8 Regression] ICE: unable to find a register to spill in class 'R0_REG'

[gjl at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54814

             Bug #: 54814
           Summary: [4.8 Regression] ICE: unable to find a register to
                    spill in class 'R0_REG'
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code, ra
          Severity: normal
          Priority: P3
         Component: other
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: gjl@gcc.gnu.org
                CC: eric.weddington@atmel.com
            Target: avr


Created attachment 28358
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28358
spills.txt: Hundreds of Spill Fails

The testsuit throws hundreds of spill fails when running against the avr cross
compiler.

The testsuite used to produce about ~5 spill fails with avr-gcc.

The strange with these spill fails is that they report register class RO_REG
which contains just one fixed register.

./gcc/testsuite/gcc.c-torture/compile/20010426-1.c:19:1: error: unable to find
a register to spill in class 'R0_REG'

./gcc/testsuite/gcc.c-torture/compile/20040121-1.c:41:1: error: unable to find
a register to spill in class 'R0_REG'

...

For a complete list see attachment.



== configure ==

SVN trunk r192090 from today (2012-10-04)

$ ../../gcc.gnu.org/trunk/configure --target=avr
--prefix=/local/gnu/install/gcc-4.8 --disable-nls --with-dwarf2
--enable-target-optspace=yes --enable-languages=c,c++