integration in CAS

[parisse]

Complex on the Prime means variables are complex variables. It is not recommended to check it unless you know exactly what you do, because it leads to fairly complex answers. There should be a warning about that when you run the integral.
I tried simplify on the answer in Xcas, I could interrupt it therefore I guess it's a Prime specific problem if it reboots, perhaps because there is not enough ram available.
I'll have a look about re/im(Si()) that are introduced when simplify is run over int(sin(sqrt(x)^-1)) (if complex_variables is set to the default 0 value).