[m-users.] Too Slow

[Julien Fischer]

Hi Peter,

On Sat, 2 May 2015, Peter Wang wrote:

> On Fri, 1 May 2015 23:23:49 +1000, Mark Brown <mark at mercurylang.org> wrote:
>>
>> Unfortunately, libtommath falls into this category - it expects
>> mp_ints to be cleared when they're done with. So the code still leaks
>> even with the above changes.
>
> It's not very convenient, but libtommath does provide a way to override
> the allocation functions that it uses: by defining the preprocessor
> symbols XMALLOC/XREALLOC/XCALLOC/XFREE when building the library, e.g.
>
>    CFLAGS='-DXMALLOC=MR_GC_malloc -DXREALLOC=MR_GC_realloc \
> 	    -DXCALLOC=MR_GC_calloc -DXFREE=GC_free' make

That might cause a few problems given that there is (currently) no such
function as MR_GC_calloc! ;-)

Also, defining those macros on the command line is going to be a PITA
for clients of the libtommath binding.  It would be better done inside a
foreign_decl pragam, just before the inclusion tommath.h (suitably
protected by checks that the macros are not already defined).

Of course, the above definitions will also only work so long as
libtommath doesn't store any pointers to GC allocated memory in non-GC
allocated memory.

Cheers,
Julien.