llvm-project

31786ee8 - [flang] Avoid undefined behaviour in Interval::Contains (#147505)

[flang] Avoid undefined behaviour in Interval::Contains (#147505) If the size of the other Interval was 0, (that.size_ - 1) would wrap below zero. I've fixed this so that a zero size interval A is within interval B if the start of A is within B. There's a few ways you could handle zero sized intervals in theory but this one passes all tests so I assume it's the intention. This fixes the following tests when ubsan is enabled: Flang :: Lower/OpenMP/PFT/sections-pft.f90 Flang :: Lower/OpenMP/derived-type-allocatable.f90 Flang :: Lower/OpenMP/privatization-proc-ptr.f90 Flang :: Lower/OpenMP/sections.f90 Flang :: Parser/OpenMP/sections.f90 Flang :: Semantics/OpenMP/clause-validity01.f90 Flang :: Semantics/OpenMP/if-clause.f90 Flang :: Semantics/OpenMP/parallel-sections01.f90 Flang :: Semantics/OpenMP/private-assoc.f90