libthr does not obey WITHOUT_SYSCALL_COMPAT

Daniel Eischen deischen at
Mon Mar 9 05:00:27 PDT 2009

On Mon, 9 Mar 2009, David Xu wrote:

> Daniel Eischen wrote:
>> On Mon, 9 Mar 2009, David Xu wrote:
>>> I don't know when it appeared. Would this patch eliminate the shit ?
>> I think so.  But I think for future ABI changes to cancellation
>> points, wouldn't we need syscall wrappers in libc?  Reason, libc
>> and libthr are now symbol-versioned, so there will no longer be
>> library bumps for ABI changes.  But if a syscall is a cancellation
>> point and libthr has to play games with it, like fcntl, I think
>> there should be a wrapper around it in libc.  If the ABI changes,
>> then both libc and libthr would need to provide a compat version
>> for it.  I think.  ;-)
> Yes, it is better to use versioning instead, I don't know why fcntl_compat is 
> there without using this feature.

Hmm, looking a little closer at this...  It looks like there
is a wrapper for fcntl in libc (libc/sys/fcntl.c).  But I think
it should always be built.  Currently, it is hidden behind
WITHOUT_SYSCALL_COMPAT in libc/sys/Makefile.  But it never calls
an older fcntl syscall.  It just transforms the old style struct
into new style, then calls the new fcntl syscall.

So I think the mistake is building fcntl.c conditionally, when
it should always be built regardless of WITHOUT_SYSCALL_COMPAT
being defined or not defined.


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