Re: [dpdk-dev] [PATCH v3 1/4] eal: disable function versioning on Windows

[Thomas Monjalon <thomas@monjalon.net>]

05/07/2020 10:51, Fady Bader:
> From: Thomas Monjalon <thomas@monjalon.net>
> > 05/07/2020 09:00, Fady Bader:
> > > > On 30/06/2020 11:49, Kinsella, Ray wrote:
> > > > > On 22/06/2020 12:55, Fady Bader wrote:
> > > > >> --- a/lib/librte_eal/include/rte_function_versioning.h
> > > > >> +++ b/lib/librte_eal/include/rte_function_versioning.h
> > > > >> @@ -11,6 +11,10 @@
> > > > >>  #error Use of function versioning disabled, is
> > "use_function_versioning=true"
> > > > in meson.build?
> > > > > Do we need a meson error/rule that catches if people explicitly
> > > > > try to enable
> > > > function_versioning.
> > > > > We don't want to just silently fail under such circumstances?
> > > > >
> > > > > Would something in lib/meson.build would work better?
> > > > >
> > > > > if use_function_versioning and target_machine.system == "Windows"
> > > > > 	// complain loudly ...
> > > > > endif
> > > > >
> > >
> > > I think this would be a better approach.
> > > But instead of checking if the use of function versioning is enabled
> > > under Windows and then complain, I think we should simply disable it
> > > from Windows in the meson.build file. Something like this:
> > >
> > > if target_machine.system == "Windows"
> > > 	use_function_versioning = false
> > > endif
> > 
> > Did you try?
> > 
> > If you disable function versioning, compilation will fail with the #error message
> > above, right?
> >
> 
> Yes, the compilation fails, we can also change the rte_function_versioning.h
> code in order not to fail under Windows.
> What do you think ?

Function versioning CANNOT be supported currently on Windows.
Function versioning macros are MANDATORY in some libraries.
That's why I think the only path is to have a specific
implementation of the function versioning macros for Windows.