Commit Briefs
all: fix or silence various gcc warnings
As usual, gcc finds some real problems but also reports a ton of noise. Fix the problems and quiet the noise.
fix gcc 4.8 warnings
LGTM=rsc R=rsc https://codereview.appspot.com/33240044
fix clang warnings reported by Tuncer Ayaz
R=rsc http://codereview.appspot.com/6744054