clang has more warnings enabled by default. Turn them off unless W is
set. This patch fixes a logic bug where warnings in clang were disabled
when W was set.
Signed-off-by: NBehan Webster <behanw@converseincode.com>
Signed-off-by: NJan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: NMark Charlebois <charlebm@gmail.com>
Cc: bp@alien8.de
Signed-off-by: NMichal Marek <mmarek@suse.cz>