with -O between -Og, -O0 and -O2 it gives 1:300 - pass:fail
Chances for pass are increased by running or turning off any GL app.. for this
case I always get one or two "pass".

With CFLAGS="-ggdb -pg -g -Og -gdwarf-2 -gstrict-dwarf" I mostly getting more
pass for turning GL app on/off (about 3-4)

Command to test:
$ while true; do sleep 0.03 &&
/projects/piglit/bin/gl-3.2-layered-rendering-clear-color-all-types 3d
single_level -fbo -auto | grep pass; done