Continuous technology scaling has resulted in an increase in both, the power density as well as the variation in device dimensions (process variations) of the manufactured processors. Both power density and process variations have a significant impact on the leakage power. Therefore, power optimization techniques should be sensitive to the variation in leakage power due to both temperature as well as process variations. Operation to Functional Units Binding Mechanism (OFBM) is the mechanism to dynamically issue operations to Functional Units (FUs) in superscalar processors. We propose a Leakage-Aware OFBM (LA-OFBM), which is both temperature and process variation aware. Our experimental results demostrate that LA-OFBM reduces the mean and standard deviation of the total energy consumption of ALUs by 18%, and 46% respectively, as compared to the traditional OFBM, without any performance penalty.