Reproducible (minimal ?) need for two compileAttributes() runs

[eddelbuettel]

This comes courtesy of a colleague. If one does

1. Create 'New package with Rcpp' followed by Build->Install+Restart -- OK
2. Add new C++ file using the examples, saved in src/ as .e.g. `src/doubleMe.src, Install+Restart -- OK
3. Now delete the initial src/rcpp_hello_world.cpp, Install+Restart --> Link error

Two runs of compileAttributes() fix it, but the IDE does not suggest it. Can we think of a heuristic to figure out when to run it twice?

[coatless]

@kevinushey already produced a reprex c.f. #733 (comment)

[eddelbuettel]

Thanks for that -- I once knew that too.

[coatless]

tl;dr of the story: the bug effects ~1% < of the developer base and is quickly solved by re-running hence there never was a push to fix it.

[eddelbuettel]

It does frustrate users.

So I am wondering if we should just run the (still very fast) compileAttributes() twice.

[eddelbuettel]

Closed via #939