smart relinking bug

[Simon Marlow]

Lemmih wrote:
> On 10/21/06, Bulat Ziganshin <bulat.ziganshin at gmail.com> wrote:
> 
>> Hello Lemmih,
>>
>> Saturday, October 21, 2006, 8:11:02 PM, you wrote:
>>
>> >> gcc -c -o a.o a.c
>> >> ghc --make Main.hs a.o
>> >>
>> >> this command incorrectly don't relinks executable if a.c was changed
>> >> but Main.hs wasn't
>>
>> > Did you mean a.o instead of a.c?
>>
>> if a.c changes then first line will recompile it and change a.o too :)
>> for '--make' command a.o will be changed and main.hs remains old
> 
> 
> Ah, I didn't read the two lines as a single command.
> 
> I think adding something like this to DriverPipeline should fix it:
> 
>        extra_ld_inputs <- readIORef v_Ld_inputs
>        extra_times <- mapM (IO.try . getModificationTime) extra_ld_inputs)
>        let linking_needed
>                | Left _  <- e_exe_time = True
>                | Right t <- e_exe_time =
>                        any (t <) (map linkableTime linkables) ||
>                        any (t <) [ t' | Right t' <- extra_times ]

Looks good - you can simplify with a ++ instead of the ||, though.

Cheers,
	Simon