Code here: https://github.com/CSHS-CWRA/RavenHydroFramework/blob/main/src/EnergyTransport.cpp#L802-L830
At line 802 we allocate hin_hist with length N=_nMinHist[p]
At 821, k runs from 0 to N-1, and at 825 m runs from 1 to N-1, but at lines 828-830 we index hin_hist at indices m-1,m and m+1, and corresponding to N-2, N-1 and N on the last loop iteration. The last one (m=N) is out of bounds, so inside of FunkyTemperatureIntegral, h3 is an undefined value
I suppose the fix is to run the m loop up to N-2 (m<=k becomes m<k), but I am not certain