Groups   191 of 99+      julia-users › It is getting harder to match function prototypes 3 posts by 2 authors      David van Leeuwen    May 2   Hello,   I am trying to get GaussianMixtuers-jl to pass the tests in julia-0.5.0-dev+3476 .  I am more and more often running into problems related to not being able to find any function to dispatch to, it seems.  This time, I am stuck with the error  MethodError: no method matching xμTΛxμ! ::Array Float64,2 , ::Array Float64,2 , ::Array Float64,1 , ::UpperTriangular Float64,Array Float64,2    Closest candidates are:    xμTΛxμ! ::Array T,2 , ::Array T,2 , ::Array T,1 , ::UpperTriangular T,S :AbstractArray T,2       The badly named `xμTΛxμ!  ` is a function in GaussianMixtures.   In this case, I can't really see which of the arguments does't match to the closest candidate.  The type `T` in the closest candidate is not specified in the function prototype, so I guess that implicitly the four `T`s in the closest candidate are, in fact, implicitly not the same type.  But even if they are implicitly the same type, the call clearly is with `T  Float64` for the five `T`s in the closest candidate.  The prototype is      function xμTΛxμ! Δ::Matrix, x::Matrix, μ::Vector, ciΣ::UpperTriangular     In julia-0.3 and julia-0.4, this problem does not occur.   Does anyone know what might be going on?    Thanks,     ---david      Stefan Karpinski    May 2   That's strange – that method appears to match what is being looked for. Have you defined your own Matrix, Vector or UpperTriangular types that might be disjoint from the ones provided by Julia??      David van Leeuwen    May 2   Not that I know.  I do have some logic to sort out UpperTriangular for versions   v 0.4.0-dev , but this does not run for julia-0.5.   It seems though, that this particular error only occurs in testing with 2 subprocesses for parallel computation.  I've made sure that the version of the code in   .julia v0.5 GaussianMixtures is the same as the codebase I am developing in.    Perhaps the processes spawned by `addprocs  ` run a different version of Julia than what I am using for testing?  Could any of these types have changed identity in such version mismatch?  I have  usr local bin julia pointing to julia-0.4 .