Galacticus won't compile - why not?

There could be many reasons for this. Read what follows for some suggestions - if none of these work, send an e-mail with as much information as possible (including any error messages reported, what OS you're using, what versions of tools such as gfortran you're using).

First, check that you're using a compatible version of gFortran. Galacticus v0.0.1 and v0.9.0 require gFortran v4.4 to compile successfully. Earlier versions of gFortran have not been tested. v4.5 of gFortran is known not to compile Galacticus because of bugs in some of the object-oriented features of the compiler. The parallel version of Galacticus, v0.9.0_gcc4.6, will compile only with gFortran v4.6 as it makes use of some of the new object-oriented features introduced in that version.