I've been busy writing a driver for a sensors chip on my new motherboard, the
driver worked ok, but I had trouble accessing it through libsensors based
programs, so I wanted to debug libsensors. However even after installing
lm_sensors-debuginfo, debugging was still inpossible.

The problem is that the current spec- (and make-) file don't pass -g to gcc when
building. Actually the current specfile doesn't pass any of the Fedora specific
CFLAGS to make, thus causing lm_sensors to be build without debuginfo,
fortifysource and stacksmashing protection.

I fixed this by adding:
export CFLAGS="%{optflags}"

Directly under %build, or you could add CFLAGS="%{optflags}" to the make command
under %build.