RE: ghc -M: module `Main' is defined in multiple files

On 21 July 2005 19:59, Ian Lynagh wrote:

> With ghc 6.4, ghc -M doesn't let me give multiple Main modules:
> 
> $ echo "module Main where main = return ()" > A.hs
> $ echo "module Main where main = return ()" > B.hs
> $ ghc -M A.hs B.hs
> module `Main' is defined in multiple files: A.hs B.hs
> 
> This worked in 6.2.2.
> 
> In neither case are any dependencies mentioning Main generated, so I
> don't think that this restriction is necessary.
> 
> This is annoying for a couple of reasons: it means I have to list all
> the executables in my Makefile twice (once for the rules, once for a
> "include .depend.Foo"), and it means that each change to a shared
> module has to regenerate the dependency files for all executables,
> which takes noticably longer.

There's a SF bug open on this one:
http://sourceforge.net/tracker/index.php?func=detail&aid=1162736&group_i
d=8032&atid=108032

Cheers,
        Simon