This is from a BLAS routine.

gfortran -O3 -g -march=athlon-xp -mfpmath=sse -mno-80387 -c ddot.f
ddot.f: In function 'ddot':
ddot.f:46: error: insn does not satisfy its constraints:
(insn 365 364 366 12 ddot.f:24 (set (reg:DF 21 xmm0 [104])
        (mem:DF (plus:SI (reg/f:SI 6 bp)
                (const_int -120 [0xffffff88])) [0 S8 A8])) 64 {*movdf_nointeger}
(nil)
    (nil))
ddot.f:46: internal compiler error: in reload_cse_simplify_operands, at
postreload.c:391
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.
$ gfortran -v ; gfortran -dumpmachine
Using built-in specs.
Configured with: ../gcc/configure --prefix=/home/ig25 --enable-languages=c,f95
Thread model: posix
gcc version 4.0.0 20050129 (experimental)
i686-pc-linux-gnu
$ cat BLAS/SRC/ddot.f
      double precision function ddot(n,dx,incx,dy,incy)
c
c     forms the dot product of two vectors.
c     uses unrolled loops for increments equal to one.
c     jack dongarra, linpack, 3/11/78.
c     modified 12/3/93, array(1) declarations changed to array(*)
c
      double precision dx(*),dy(*),dtemp
      integer i,incx,incy,ix,iy,m,mp1,n
c
      ddot = 0.0d0
      dtemp = 0.0d0
      if(n.le.0)return
      if(incx.eq.1.and.incy.eq.1)go to 20
c
c        code for unequal increments or equal increments
c          not equal to 1
c
      ix = 1
      iy = 1
      if(incx.lt.0)ix = (-n+1)*incx + 1
      if(incy.lt.0)iy = (-n+1)*incy + 1
      do 10 i = 1,n
        dtemp = dtemp + dx(ix)*dy(iy)
        ix = ix + incx
        iy = iy + incy
   10 continue
      ddot = dtemp
      return
c
c        code for both increments equal to 1
c
c
c        clean-up loop
c
   20 m = mod(n,5)
      if( m .eq. 0 ) go to 40
      do 30 i = 1,m
        dtemp = dtemp + dx(i)*dy(i)
   30 continue
      if( n .lt. 5 ) go to 60
   40 mp1 = m + 1
      do 50 i = mp1,n,5
        dtemp = dtemp + dx(i)*dy(i) + dx(i + 1)*dy(i + 1) +
     *   dx(i + 2)*dy(i + 2) + dx(i + 3)*dy(i + 3) + dx(i + 4)*dy(i + 4)
   50 continue
   60 ddot = dtemp
      return
      end

Line 46 is the '50 continue' line.

        Thomas