[lno] Bootstrap failure on Alpha due to miscompilation

[Falk Hueffner <hueffner at informatik dot uni-tuebingen dot de>]

Hi,

lno fails to bootstrap on Alpha for several days now; it segfaults
while compiling libgcc in the second stage, so apparently it
miscompiles itself.

The only test suite failure that does not already occur on mainline
Alpha or on lno ia64 (according to gcc-testresults) is
gcc.c-torture/execute/961017-1.c. There, lno compiles at -O and above

  unsigned char z = 0;
  do ;  while (--z > 0);

to a loop over the whole 64 bit space:

        clr $1
        [...]
$L2:    lda $1,1($1)
        bne $1,$L2

I'm not sure, however, whether it is this problem that causes the
bootstrap failure (people don't often rely on unsigned wrapping
semantics in loops...).

-- 
	Falk