[Bug other/20586] New: bootstrap comparision fails with -funroll-loops.

["pluto at pld-linux dot org" <gcc-bugzilla at gcc dot gnu dot org>]

In theory, the last two should stages produce the same results,   
which `make compare` can check.   
  
With CFLAGS:  
-march=i686 -mtune=pentium4 -O2 -fomit-frame-pointer -funroll-loops  
   
Comparing stage2 and stage3 of the compiler    
(...)    
Bootstrap comparison failure!    
./bb-reorder.o differs    
./builtins.o differs    
./caller-save.o differs    
./calls.o differs    
./combine.o differs    
./cse.o differs    
./ddg.o differs    
./dwarf2out.o differs    
./flow.o differs    
./global.o differs    
./loop.o differs    
./real.o differs    
./recog.o differs    
./reg-stack.o differs    
./regclass.o differs    
./regrename.o differs    
./reload.o differs    
./reload1.o differs    
./rtlanal.o differs    
./simplify-rtx.o differs    
./tree-dfa.o differs    
./tree-phinodes.o differs    
./tree-ssa-live.o differs    
./tree-ssa-loop-im.o differs    
./tree-ssa-loop-ivopts.o differs    
./tree-vect-transform.o differs    
ada/ali.o differs    
ada/binde.o differs    
ada/bindgen.o differs    
ada/checks.o differs    
ada/exp_aggr.o differs    
ada/exp_ch5.o differs    
ada/g-speche.o differs    
ada/inline.o differs    
ada/s-carun8.o differs    
ada/sem_case.o differs    
ada/sem_ch3.o differs    
ada/sem_ch8.o differs    
ada/sem_maps.o differs    
ada/tree_io.o differs    
ada/uintp.o differs    
cp/mangle.o differs    
cp/pt.o differs    
build/gensupport.o differs    
make[1]: *** [gnucompare] Error 1 
 
# gcc -v 
Reading specs from /usr/lib/gcc/i686-pld-linux/4.0.0/specs 
Target: i686-pld-linux 
Configured with: ../configure --prefix=/usr --libdir=/usr/lib 
--libexecdir=/usr/lib --infodir=/usr/share/info --mandir=/usr/share/man 
--enable-shared --enable-threads=posix --enable-__cxa_atexit 
--enable-languages=c,c++,ada,java --enable-c99 --enable-long-long 
--disable-multilib --enable-nls --with-gnu-as --with-gnu-ld 
--with-demangler-in-ld --with-system-zlib --with-slibdir=/lib --without-x 
--enable-cmath --enable-libgcj --enable-libgcj-multifile 
--enable-libgcj-database --enable-gtk-cairo i686-pld-linux 
Thread model: posix 
gcc version 4.0.0 20050319 (prerelease) (PLD Linux)

-- 
           Summary: bootstrap comparision fails with -funroll-loops.
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: other
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pluto at pld-linux dot org
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pld-linux
  GCC host triplet: i686-pld-linux
GCC target triplet: i686-pld-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20586