Patch to enable GHC runtime system with thr_debug_p options...

[Simon Marlow]

On 03/12/12 20:11, Joachim Breitner wrote:
> Dear Michał,
>
> Am Sonntag, den 02.12.2012, 22:44 +0100 schrieb "Michał J. Gajda":
>> On 12/02/2012 09:20 PM, Joachim Breitner wrote:
>>>> I noticed that Ubuntu, as well as Debian and original packages come
>>>> without some variants of threaded debugging binaries.
>>>> A recent change added of printing a stack trace with -xc option requires
>>>> using both -ticky and profiling compile options,
>>>> which in turn forces program to be compiled in a -debug RTS way.
>>>> Since stack trace looks like indispensable debugging tool, and
>>>> convenient parallelization is strength of Haskell,
>>>> I wonder is there any remaining reason to leave beginners with a cryptic
>>>> error message
>>>> when they try to debug a parallel or threaded application, and want to
>>>> take advantage of stack trace?
>>>>
>>>> The resulting ghc-prof package would be increased by less than 1%.
>>>>
>>>> Here is a patch for Ubuntu/Debian GHC 7.4.2 package, as well as upstream
>
> --- ghc-7.4.2-orig/mk/config.mk.in	2012-06-06 19:10:25.000000000 +0200
> +++ ghc-7.4.2/mk/config.mk.in	2012-12-01 00:22:29.055003842 +0100
> @@ -256,7 +256,7 @@
>   #   l           : event logging
>   #   thr_l       : threaded and event logging
>   #
> -GhcRTSWays=l
> +GhcRTSWays=l thr_debug_p thr_debug
>
>   # Usually want the debug version
>   ifeq "$(BootingFromHc)" "NO"
>
>
> I notice that your patch modifies the defaults of GHC as shipped by
> upstream, and I wonder if there is a reason why these ways are not
> enabled by default.
>
> Dear GHC HQ: Would you advice against or for providing a RTS in the
> thr_debug_p and thr_debug ways in the Debian package?

thr_debug is already enabled by default.  thr_debug_p is not currently 
enabled, but only because we very rarely need it, so there wouldn't be 
any problem with enabling it by default.

Cheers,
	Simon