501760 - mmap with MAP_ANONYMOUS doesn't work on Symbian

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Makoto Kato [:m_kato]]

OpenC (http://forum.nokia.com/openc) provides mmap() function, but this doesn't support MAP_ANONYMOUS.
So NewGCChunk() on symbian is always failure.  So don't use GC_USE_MMAP on Symbian (or use RChunk)

Comment 1

[Makoto Kato [:m_kato]]

Attachment: patch v1

Comment 2

[Jim Blandy :jimb]

Comment on attachment 386689 [details] [diff] [review]
patch v1

One general comment: this patch also includes some changes to the JS_{EXTERN,EXPORT}_{API,DATA} macros; those should be a separate patch.  It's very helpful to have separate bugs for separate changes.  (Those changes look good, by the way; I will r+ them if you r? me.)

In the long run, we should be replacing these #if PLATFORM/#elif/... chains with configure.in tests.  If you're interested, I'd happily review such a patch.  But that is a bit more work.  Let me attach an alternative patch that seems clearer.

Comment 3

[Jim Blandy :jimb]

Attachment: Don't use posix_memalign or mmap on Symbian.

Could you give this a try and see if it works as well as the fix you proposed?  If we can't autoconfiscate code like this,, I'd like to at least have it evolve more towards a straightforward platform-by-platform chain of #ifs.

Comment 4

[Makoto Kato [:m_kato]]

(In reply to comment #3)
> Created an attachment (id=387024) [details]
> Don't use posix_memalign or mmap on Symbian.
> 
> Could you give this a try and see if it works as well as the fix you proposed? 
> If we can't autoconfiscate code like this,, I'd like to at least have it evolve
> more towards a straightforward platform-by-platform chain of #ifs.

Great.  No problem.

Comment 5

[Jim Blandy :jimb]

Attachment: Bug 501760: Don't try to use mmap for JS allocation on Symbian.

Revised based on IRC discussion.

When we're using jemalloc (indicated by MOZ_MEMORY being #defined), that does provide posix_memalign, so the comment in the patch is wrong if we're using jemalloc on Symbian.  However, it turns out that the right way to recognize that posix_memalign is available isn't as was suggested in IRC; the original patch should use it just fine.

Thus: comment fixed; substance unchanged.

Comment 6

[Jim Blandy :jimb]

http://hg.mozilla.org/mozilla-central/rev/603c6cb5be9a