Patch: -Wunreachable-bytecode

[Per Bothner]

Tom Tromey wrote:
> This patch adds a new -Wunreachable-bytecode warning to gcj.  I added
> this because we want to suppress these warnings in the test suite, and
> this seemed like the most straightforward approach to doing so.

Why do we want to supress it?  Is it unreachable bytecode in .class
files generated by gcj?  If so we should fix gcj to not generate
uneachable bytecode.  Is it unreachable bytecode generated by javac?
Then that is a different matter.

Gcc has too many options as it is, and we really want to avoid adding
more.
-- 
	--Per Bothner
per@bothner.com   http://www.bothner.com/per/