FWIW julia --trace-compile=stderr -e 'using Clapeyron; model = PCSAFT("water"); saturation_pressure(model, 298.0)' keeps compiling ever more complicated method signatures, related to StaticArrays.jl and ForwardDiff.jl, and the final “hang” (maybe not really a hang, perhaps there’s just too much code in the method body?) seems to be in LLVM. This was with nightly Julia.