optimization/5423: The compiler crashes and you need to relax the optimization to -O0

[Craig Rodrigues]

One more note.

In gcc 3.1, -fdce has been renamed to -fssa-dce.

If -fssa-dce is used, along with all the other

compiler flags specified in this PR, then this

file compiles at full optimization.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=5423