I am using hierarchical modules with ghc, and I have a bunch of common modules used by several projects, which should build on serveral platforms.

Now, assume I have the following:

. |-- Bar | `-- Module.hs |-- Foo | `-- Module.hs `-- Main.hs

Main imports both Bar.Module and Foo.module.

Currently I am using -osuf ARCHITECTURE.o with ghc --make, which works, but clutters the common modules directory with .o files. (I may want to keep it clean.)

So I want to redirect the output with -odir OUTPUT_DIR

However it won't work since ghc wll put the compilation output of both modules in OUTPUT_DIR/Module.o and subsequently fail to link.

Perhaps -odir should append the full module name as a directory (i.e. the default behaviour would be a special case where -odir is ".").

Is there a way to get the files named Bar.Module.o and Foo.Module.o or such? Is there a better way?

Another thing that would be good would be a way to redirect output to a directory relative to where the source file is, say for instance that the output of Bar/Module.hs should be put in Bar/ARCHITECTURE/Module.o and the output of Foo/Module.hs should be put in Foo/ARCHITECTURE/Module.o.

It sounds like what you want is a way to specify a general mapping function from module names to object file names, perhaps in Haskell. Something like $ ghc -omap "\m -> $ARCHITECTURE ++ \ map (\x -> if x == '.' then '/' else x) m ++ \ \".o\"" I'm only kidding, but we could implement this if we wanted :-) How about having a make rule which just moves the object file to the required place after compilation? Cheers, Simon