I updated my code so that it now acquires a lock before calling claim_file if v0. https://github.com/rui314/mold/commit/54fedf005fb35acdcb0408395aa403f94262190a
On Mon, Jul 11, 2022 at 8:51 PM Martin Liška <mli...@suse.cz> wrote: > > On 7/11/22 14:24, Rui Ueyama wrote: > > I updated my patch to support the proposed API: > > https://github.com/rui314/mold/commit/22bbfa9bba9beeaf40b76481d175939ee2c62ec8 > > > > Martin, > > > > I think you want to apply this patch. Currently, your API always > > passes LAPI_V0 as the maximum API version. > > Are you sure? > > The function signature is: > > (*ld_plugin_get_api_version) (const char *plugin_identifier, > const char *plugin_version, > enum linker_api_version minimal_api_supported, > enum linker_api_version maximal_api_supported, > ... > > Which means the plug-in always set minimal as LAPI_V0 and maximal > LAPI_V0/V1. That seems correct to me. I'm sorry I misunderstood your code. It looks correct. > Martin > > > > > > diff --git a/lto-plugin/lto-plugin.c b/lto-plugin/lto-plugin.c > > index e9afd2fb76d..c97bda9de91 100644 > > --- a/lto-plugin/lto-plugin.c > > +++ b/lto-plugin/lto-plugin.c > > @@ -1441,15 +1441,15 @@ negotiate_api_version (void) > > const char *linker_version; > > > > enum linker_api_version supported_api = LAPI_V0; > > #if HAVE_PTHREAD_LOCKING > > supported_api = LAPI_V1; > > #endif > > > > - api_version = get_api_version ("GCC", BASE_VERSION, LAPI_V0, > > + api_version = get_api_version ("GCC", BASE_VERSION, LAPI_V1, > > supported_api, &linker_identifier, > > &linker_version); > > if (api_version > supported_api) > > { > > fprintf (stderr, "requested an unsupported API version (%d)\n", > > api_version); > > abort (); > > } > > > > On Mon, Jul 11, 2022 at 6:51 PM Martin Liška <mli...@suse.cz> wrote: > >> > >> On 7/11/22 11:55, Richard Biener wrote: > >>> On Mon, Jul 11, 2022 at 11:16 AM Alexander Monakov <amona...@ispras.ru> > >>> wrote: > >>>> > >>>> On Mon, 11 Jul 2022, Rui Ueyama wrote: > >>>> > >>>>>> but ignoring min_api_supported is wrong, and assuming > >>>>>> max_api_supported > 0 > >>>>>> is also wrong. It really should check how given [min; max] range > >>>>>> intersects > >>>>>> with its own range of supported versions. > >>>>> > >>>>> Currently only one version is defined which is LAPI_V1. I don't think > >>>>> LAPI_UNSPECIFIED is a version number; rather, it's an unspecified > >>>>> value. No ordering should be defined between a defined value and an > >>>>> unspecified value. If LAPI_UNSPECIFIED < LAPI_V1, it should be renamed > >>>>> LAPI_V0. > >>>> > >>>> You still cannot rely on API guarantees of LAPI_V1 when the plugin does > >>>> not > >>>> advertise it (thread safety of claim_file in this particular case). > >>> > >> > >> Hi. > >> > >> All right, I think we should rename LAPI_UNSPECIFIED to LAPI_V0 in order > >> to support minimal_api_supported == LAPI_V0. > >> > >>> So with LAPI_UNSPECIFIED all the plugin gets is the linker name and > >>> version. > >>> Clarifying the documentation on LAPI_UNSPECIFIED might be nice, also > >>> what the expectation is on the linker when the plugin returns > >>> LAPI_UNSPECIFIED when it speficied minimal_api_supported == V1. > >> > >> I've clarified that linker should return a value that is in range > >> [minimal_api_supported, maximal_api_supported] and added an abort > >> if it's not the case. > >> > >> Having that, mold should respect if maximal_api_supported == LAPI_V0 is > >> returned > >> by a plug-in (happens now as we miss locking for some targets). > >> > >> Martin > >> > >>> "minimal_api_supported == LAPI_UNSPECIFIED" does not make much > >>> sense if using Ruis reading of this value? > >>> > >>>> And you still should check the intersection of supported API ranges > >>>> and give a sane diagnostic when min_api_supported advertised by the > >>>> plugin > >>>> exceeds LAPI_V1 (though, granted, the plugin could error out as well in > >>>> this > >>>> case). > >>>> > >>>> Alexander >
