Thanks to the pointers given I dug a little bit under the hood ad found the promising unbox intrinsic function. It would exactly be what I was looking for but it seems to work only one way:
*julia> **using Base.Intrinsics* *julia> **theFloat=1.0* *1.0* *julia> **b=unbox(Int64,theFloat)* *4607182418800017408* *julia> **bits(theFloat)* *"0011111111110000000000000000000000000000000000000000000000000000"* *julia> **type Words2x32* * lo::Int32* * hi::Int32* * end* *julia> **c=Words2x32(0,1072693248)* *Words2x32(0,1072693248)* *julia> **d=unbox(Float64,c)* *1.0* *julia> **bits(d)* *"0011111111110000000000000000000000000000000000000000000000000000"* *julia> **e=unbox(Words2x32,d)* *Segmentation fault: 11* *Is it a bug or I have used the function in an unexpected way?*