test: Use global variables to defeat gccgo optimizer.
test: Use global variables to defeat gccgo optimizer.

The gccgo compiler is smart enough to not make something which
is not used.  Use global variables to defeat this
optimization.

R=rsc
CC=golang-dev
http://codereview.appspot.com/2129041

tv42/old-go,dsriram/golang,pombredanne/go-deleteme,pombredanne/go-deleteme,pombredanne/go-deleteme,dsriram/golang,pombredanne/go-deleteme,gnanderson/go,tv42/old-go,apparentlymart/golang,h8liu/golang,gnanderson/go,dsriram/golang,gnanderson/go,ssrl/go,tv42/old-go,apparentlymart/golang,h8liu/golang,dsriram/golang,apparentlymart/golang,h8liu/golang,h8liu/golang,tv42/old-go,dsriram/golang,h8liu/golang,ssrl/go,ssrl/go,gnanderson/go,apparentlymart/golang,ssrl/go,gnanderson/go,ssrl/go,ssrl/go,tv42/old-go,dsriram/golang,ssrl/go,gnanderson/go,tv42/old-go,gnanderson/go,h8liu/golang,apparentlymart/golang,pombredanne/go-deleteme,pombredanne/go-deleteme,tv42/old-go,pombredanne/go-deleteme,dsriram/golang,h8liu/golang,apparentlymart/golang,apparentlymart/golang