Error building gcc9

[Brook Milligan <brook%nmsu.edu@localhost>]

I’m trying to build gcc9 using gcc8 from pkgsrc, and get the following error:

../../gcc-9.2.0/gcc/plugin.c: In function 'bool try_init_one_plugin(plugin_name_args*)':
../../gcc-9.2.0/gcc/plugin.c:700:42: error: 'RTLD_NOW' was not declared in this scope
   dl_handle = dlopen (plugin->full_name, RTLD_NOW | RTLD_GLOBAL);

Pkgsrc is set to build everything with gcc8 from pkgsrc and that has seemed to work fine for over 500 packages, so I think the basic setup is ok.

I presume the error is not including dlfcn.h somewhere, but it is hard to believe this would not show up earlier and I have no idea where in the tangle of header files to look.

I would appreciate any thoughts on how to overcome this.

Thanks a lot.

Cheers,
Brook