An apparatus includes a plurality of macrocells (402-406) formed from logic capable of performing one or more functions. The apparatus also includes a clock tree (408) capable of receiving a clock signal and providing at least one copy of the clock signal to each macrocell. The clock tree includes a local branch (410-414) within each macrocell, where each local branch is capable of providing at least one copy of the clock signal. In addition, the apparatus includes at least one glitch detection circuit capable of detecting (418) a glitch in one or more copies of the clock signal provided by the local branches in the macrocells.