A system, method, and computer program product for optimizing thread stack memory allocation is disclosed. The method includes the steps of receiving source code for a program, translating the source code into an intermediate representation, analyzing the intermediate representation to identify at least two objects that could use a first allocated memory space in a thread stack memory, and modifying the intermediate representation by replacing references to a first object of the at least two objects with a reference to a second object of the at least two objects.