We present a static analysis by Abstract Interpretation to check for run-time errors in parallel C programs. Following our work on Astrée, we focus on embedded critical programs without recursion nor dynamic memory allocation, but extend the analysis to a static set of threads. Our method iterates a slightly modified non-parallel analysis over each thread in turn, until thread interferences stabilize. We prove the soundness of the method with respect to a sequential consistent semantics and a reasonable weakly consistent memory semantics. We then show how to take into account mutual exclusion and thread priorities through partitioning over the scheduler state. We present preliminary experimental results analyzing a real program with our prototype, Thésée, and demonstrate the scalability of our approach.