[update] lang/gcc10-devel add new plugin support option

[gerald]

Summary

Some few ports might have some use, for instance AFL/AFL++ for the gcc wrapper fast mode.

[devnexen_gmail.com]

I started with one gcc flavour only to see if it can appeal.

[gerald]

In D22292#487463, @devnexen_gmail.com wrote:

I started with one gcc flavour only to see if it can appeal.

This makes sense, and I recommend to stay with gcc10-devel (as it is going to lead
to gcc10 next year) and perhaps gcc9 as the default version of GCC.

Definitely a good approach to start from the most current.

[gerald]

I believe this can (and should) be simplified to

PLUGINS_CONFIGURE_ARGS=plugin

instead of

.if ${PORT_OPTIONS:MPLUGINS}
CONFIGURE_ARGS+=--enable-plugin
.endif

Can you please see whether that still works for you?

[gerald]

Per my previous comment. Note I actually meant PLUGINS_CONFIGURE_ENABLE, and use that in this patch.

[gerald]

Fixed patch (option helpers need to come earlier in the Makefile) that I am testing now.

[devnexen_gmail.com]

In D22292#487603, @gerald wrote:

Fixed patch (option helpers need to come earlier in the Makefile) that I am testing now.

Works for me . Thanks

[gerald]

Thanks for proposing this. As I mentioned in the commit I plan on making the same change to
lang/gcc9-devel and later lang/gcc9 as well.