Re: (ITS#8034) lmdb-0.9.14 | Undefined symbols for architecture ppc: "_posix_memalign" referenced from _mdb_env_copyfd2 | ld: symbol(s) not found for architecture ppc

[hyc@symas.com]

Hallvard Breien Furuseth wrote:
> On 23/01/15 18:10, hyc@symas.com wrote:
>>> LMDB should not be pulled separately from OpenLDAP.  I.e., only the
>>> bundled
>>> version of LMDB should be used with a given version of OpenLDAP.
>>
>> I've already had this conversation with the gentoo maintainers; they
>> refuse to listen to reason. It's all their problem now.
>
> Still, memalign() is a problem.  mdb.c defines HAVE_MEMALIGN,
> but it may be wrong for the user to -D"HAVE_MEMALIGN" since that
> may omit whatever #include file declares it. <malloc/malloc.h>
> (some Apple stuff I think), <malloc.h> dunno what else.
>
> We could drop memalign.  malloc(desired space + 1 OS page), then
> adjust for alignment.  On machines with a sane linear address
> space where we can tell alignment from the address, anyway.

Such an address space is already a requirement for LMDB, since mmaps are 
page-aligned.
>
> On weirder hosts, you care about them, omit alignment altogether
> if posix_memalign is missing.  And omit O_DIRECT/F_NOCACHE in
> mdb_env_copy2().  I gather those are why we need alignment.

Right.

> Branch "mdb/memalign" in <git://git.uio.no/u/hbf/openldap.git>
> has draft code.

Still don't have time to check this myself, may have an opportunity 
tomorrow.
>
> Daniel: You can try that branch, and configure with
> CPPFLAGS="-DMDB_MEMALIGN_METHOD=2".
>
>
> I guess the preprocessor test should be "defined(a test for
> Darwin: __APPLE__, _MACOSX_ or..?)" and not __PPC__.  PowerPC is
> an architecture, while features like posix_memalign are defined
> by compilers/operating systems.  The macports issue disables mdb
> for Darwin.  Or maybe not, I don't know Mac, Darwin, PPC or
> Gentoo, or if you just said this has been resolved, so I'll stay
> out of of that issue.
>
Right. I thought you (OP) were talking about Gentoo Linux on PPC, not 
MacOSX on PPC. Linux on PPC should be using the same glibc as any other 
architecture, and as such ought to already have posix_memalign.

-- 
   -- Howard Chu
   CTO, Symas Corp.           http://www.symas.com
   Director, Highland Sun     http://highlandsun.com/hyc/
   Chief Architect, OpenLDAP  http://www.openldap.org/project/