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The core does not > raise an exception if there is a division by zero (for either integer or > floating point division). floating-point division by zero signals the FE_DIVBYZERO exception. you can test this via fetestexcept(FE_DIVBYZERO). integer operations must not affect fenv status flags so integer division by zero does not do that. if you want to *trap* division by zero, there is no reliable way to do that in c (this is not related to particular cpus though).