On Tue, Mar 24, 2020 at 02:16:32PM -0500, Eric Blake wrote:
On 3/24/20 1:54 PM, Richard W.M. Jones wrote:
>On Tue, Mar 24, 2020 at 01:43:52PM -0500, Eric Blake wrote:
>>On 3/21/20 7:06 AM, Richard W.M. Jones wrote:
>>>Eric:
>>>
>>>Yifan Gu has posted a few patches for mingw support. My comments
>>>below.
>>>
>>>https://github.com/gyf304/nbdkit/commit/a37c4ca6546dfc4e96e305af97b62e5a9d6174ca
>>>
>>>* I think the SHARED_LDFLAGS idea is good. I pushed a slightly
>>> different take on the idea here:
>>>
https://github.com/libguestfs/nbdkit/commit/1d634009ab8e43592065ec469df63...
>>> It's slightly different from what Yifan posted above, because I
>>> replaced -module -avoid-version -shared with $(SHARED_LDFLAGS),
>>> adding -no-undefined additionally on mingw.
>>
>>Why are we trying to avoid -no-undefined on other platforms?
>
>Isn't it because we rely on it, since our plugins need symbols that
>are undefined at link time such as nbdkit_*?
Yes, at the moment they do, but do they need to? We could ship
libnbdkit which provides just the symbols that plugins can link
against, and then link our binary nbdkit against that same library,
rather than expecting our plugins to compile undefined until loaded
by our binary. In other words, if the fix is by separating our
public functions into a shared library for mingw to compile plugins
without undefined symbols, why not do the same for all platforms?
(For non-mingw platforms) this breaks the source API promises rather
seriously, so if I understand your proposal correctly I don't think
this is a good idea. It's possibly something we can consider for
internal plugins, or for the V3 API.
Rich.
--
Richard Jones, Virtualization Group, Red Hat
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