<html><head></head><body><div class="gmail_quote">Am 1. Mai 2015 14:23:49 MEZ, schrieb Mark Brown <mark@mercurylang.org>:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <pre class="k9mail">On Fri, May 1, 2015 at 5:54 PM, Peter Wang <novalazy@gmail.com> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #729fcf; padding-left: 1ex;"> On Fri, 01 May 2015 07:02:48 +0100, Matthias Guedemann <matthias.guedemann@googlemail.com> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #ad7fa8; padding-left: 1ex;"> Hi Peter, <blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #8ae234; padding-left: 1ex;"> You should allocate the mp_ints like this: </blockquote> <blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #8ae234; padding-left: 1ex;"> Mp_Int = MR_GC_NEW_ATTRIB(mp_int, MR_ALLOC_ID); </blockquote> <blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #8ae234; padding-left: 1ex;"> For the string in mp_to_string you should use </blockquote> <blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #8ae234; padding-left: 1ex;"> MR_allocate_aligned_string_msg(S, length, MR_ALLOC_ID); </blockquote> <blockquote class="gmail_quote" style="margin: 0pt 0pt 1ex 0.8ex; border-left: 1px solid #8ae234; padding-left: 1ex;"> or other macros in mercury_string.h </blockquote> ok, thank you for the hints. Could you point me to the relevant section in the user guide, or is the documentation only in the source files? </blockquote> Unfortunately the latter (mercury_memory.h and mercury_string.h). I think no memory management interface has been documented because the existing interface is specific to conservative GCs, if not Boehm GC. Nonetheless, practical code using the foreign language interface invariably needs to allocate so I think we should document some of the macros and functions, with caveats. </blockquote> That's done for lists and floats (section 14.3.1), and ought to be done for strings, too. Allocating foreign types on Mercury's heap needs one big caveat, though, namely that no finaliser will be called. If the foreign type needs to be explicitly freed, allocating it on Mercury's heap won't work. 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. Cheers, Mark. <hr /> users mailing list users@lists.mercurylang.org <a href="https://www.mercurylang.org/lists/listinfo/users">https://www.mercurylang.org/lists/listinfo/users</a> </pre></blockquote></div> Hi Mark, thanks for the info. I'll add predicates to clear mp_int values which call the finalizers. Is this because mp_int is just a struct containing pointers to malloc'ed memory? So then the GC frees the memory malloc'ed for mp_int itself, and the internal stays stay allocated? Matthias</body></html>