Compilation

Cactus can be built in different configurations from the same copy of the source files, and these different configurations coexist in the Cactus/configs directory. Here are several instances in which this can be useful:

1. Different configurations can be for different architectures. You can keep executables for multiple architectures based on a single copy of source code, shared on a common file system.
2. You can compare different compiler options, and debug-modes. You might want to compile different communication protocols (e.g. MPI or Globus), or leave them out all together.
3. You can have different configurations for different thorn collections compiled into your executable.

Once a configuration has been created by gmake <config>, as described in detail in the next section, a single call to gmake <config> will compile the code. The first time, it generates a compile ThornList, and gives you the chance to edit it before continuing.