On Sat, May 18, 2013 at 1:22 PM, Roland Mainz <[email protected]> wrote: > On Fri, May 17, 2013 at 4:48 PM, Irek Szczesniak <[email protected]> > wrote: >> On Fri, May 17, 2013 at 2:52 AM, Roland Mainz <[email protected]> >> wrote: >>> Attached (as "valgrind381_libast_allocator001.diff.txt") is a patch >>> for valgrind 3.8.1 which enables valgrind (again) to recognise the >>> libast memory allocator (long ago it worked out-of-the-box but somehow >>> it got broken). >>> >>> The basic idea of the fix is to teach valgrind that the matching >>> memory allocation/deallocation functions are prefixed with |_ast_*()|. >> >> Just curious - how long did it take to figure that valgrind is broken > > I know that since a month for so because some things which didn't work > should've triggered valgrind... > >> for AST and to make the fix? > > The prototype fix mainly needed a lot of digging+research (and > gnaw'ing off my fingernails to figure out how valgrind works... maybe > eight manhours or something like that... > ... the research digged out some issues with valgrind which have to be > addressed from their side in the future: > 1. valgrind needs support for multiple, independent memory allocators > operating in the same process. Right now it operates in "one allocator > to rule them all"-mode and doesn't properly detect issues when memory > obtained via |_chicken_malloc()| is passed to |_fish_free()| (instead > of |_chicken_free()|)). This is *lots* of work and may require some > restructuring how "valgrind"'s "memcheck" tool works (that's around > 2-3 manmonths of work... without support for "nested" memory pools). > 2. We need the ability to configure "valgrind" to recognise > alternative names for |malloc()|, |realloc()|, |free()|, > |posix_memalign()| via command line options or an options file > (interestingly Google concurrently hit the same issue with similar > solutions - see http://code.google.com/p/valgrind-variant/). > > I'm going to discuss that with the "valgrind" people when I have time...
Erm... Glen/Irek: Do you have any feedback on the valgrind patch ? ---- Bye, Roland -- __ . . __ (o.\ \/ /.o) [email protected] \__\/\/__/ MPEG specialist, C&&JAVA&&Sun&&Unix programmer /O /==\ O\ TEL +49 641 3992797 (;O/ \/ \O;) _______________________________________________ ast-developers mailing list [email protected] http://lists.research.att.com/mailman/listinfo/ast-developers
