[xmonad] darcs patch: Clean .hi and .o files when recompiling

[Gwern Branwen]

On Wed, Sep 9, 2009 at 6:51 PM, Spencer Janssen
<spencerjanssen at gmail.com> wrote:
> On Wed, Sep 09, 2009 at 10:18:39AM +0200, Joachim Breitner wrote:
>> Hi,
>>
>> I???d like to see this in the next release, to reduce the delta between xmonad as
>> shipped by debian and as it is on hackage:
>
> Maybe I missed the original patch (I haven't paid much attention to xmonad in
> the past two months), but I would really appreciate seeing patches when/before
> they're applied downstream.  If the fix is important enough to apply in Debian,
> it is probably important enough to at least consider upstream.
>
> Speaking of "delta", are there any other non-integration patches that Debian
> applies?
>
>> Wed Sep  9 10:15:57 CEST 2009  Joachim Breitner <mail at joachim-breitner.de>
>>   * Clean .hi and .o files when recompiling
>>   This patch is applied to the Debian packages since a few months. During the
>>   last ghc upgrade in Debian, people had to this manually to get their xmonad
>>   compilable again. This patch should mitigate this a bit.
>
> Regarding this specific change, perhaps we can delete interface and object
> files immediately after compiling?  We already instruct GHC to ignore them, so
> they're just taking up disk space.  Even better, can we tell GHC to put those
> files in /tmp and clean them up when compilation is done?

We might be able to. Looking at
http://www.haskell.org/ghc/docs/latest/html/users_guide/separate-compilation.html#temp-files

I see that what it calls 'temporary files' are already going into
/tmp; what we want is to redirect the interface and object files,
which would be done with "-odir" and "-hidir". So maybe

hunk ./XMonad/Core.hs 460
-            waitForProcess =<< runProcess "ghc" ["--make",
"xmonad.hs", "-i", "-ilib", "-fforce-recomp", "-v0", "-o",binn] (Just
dir)
+            waitForProcess =<< runProcess "ghc" ["--make",
"xmonad.hs", "-i", "-ilib", "-fforce-recomp", "-hidir", "/tmp",
"-odir", "/tmp", "-v0", "-o",binn] (Just dir)

? (Can we hardcode /tmp?)

If I understand the docs right, this ought to redirect all interface &
object files, including anything in .xmonad/lib.

-- 
gwern