[Rcpp-devel] gcc 10 error: symbol `fun' is already defined

[Iñaki Ucar]

FYI, reported here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93643

On Sun, 9 Feb 2020 at 12:14, Iñaki Ucar <iucar at fedoraproject.org> wrote:
>
> BTW, I've noticed that, if you remove the extern "C" declaration and
> compile your example as C code with gcc 9.2.1, there's a warning:
>
> broken.c:16:16: warning: ‘f’ is static but declared in inline function
> ‘f2’ which is not static
>   16 |  static void (*f)();
>      |                ^
> broken.c:9:16: warning: ‘f’ is static but declared in inline function
> ‘f1’ which is not static
>    9 |  static void (*f)();
>      |                ^
>
> and then the linker fails with undefined references to f1 and f2.
> Declaring f1 and f2 as static inline solves the issue in C and also in
> C++ for gcc 10.
>
> Maybe it would be better to declare those RcppEigen stubs as static inline?
>
> Iñaki
>
> On Sun, 9 Feb 2020 at 11:47, Iñaki Ucar <iucar at fedoraproject.org> wrote:
> >
> > On Sun, 9 Feb 2020 at 03:36, Kevin Ushey <kevinushey at gmail.com> wrote:
> > >
> > > Here's an example program that fails to compile with gcc-10 for me:
> > >
> > > https://gist.github.com/kevinushey/cfa848be2d39ddd110f893d9b6c5ac9c
> > >
> > > So I think we can conclude this is a gcc-10 bug. It also fails with
> > > the contracts branch of gcc on godbolt (although with a different
> > > error):
> > >
> > > https://godbolt.org/z/dowsE5
> > >
> > > But gcc trunk seems okay.
> >
> > Thanks for looking into this. Now I'm more confident bringing this upstream.
> >
> > Iñaki
>
>
>
> --
> Iñaki Úcar



-- 
Iñaki Úcar