Fix overflow in computation of constraint_median with 32-bit time_t #74
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Adding two time_t values representing the current time overflows if the underlying type is a 32 bit integer. Use long long for the addition which should always consist of at least 64 bit. This fixes constraints erroneously considered invalid due to an incorrectly computed median.
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On system where
time_tis a signed 32-bit integer (e.g., glibc on 32-bit x86), currently the computation ofconf->constraint_mediancauses an integer overflow. Subsequently, all time sources are considered invalid due to a high deviation from the constraint.This PR adds a patch that uses
long longfor the computation, which fixes this issue with 32-bit x86 glibc and should not harm other systems. If the cast should be avoided, an alternative with slightly larger rounding error would be something like