Auto merge of #37732 - jseyfried:use_extern_macros, r=nrc

Support `use`ing externally defined macros behind `#![feature(use_extern_macros)]`

With `#![feature(use_extern_macros)]`,
 - A name collision between macros from different upstream crates is much less of an issue since we can `use` the macros in different submodules or rename with `as`.
 - We can reexport macros with `pub use`, so `#![feature(macro_reexport)]` is no longer needed.
 - These reexports are allowed in any module, so crates can expose a macro-modular interface.

If a macro invocation can resolve to both a `use` import and a `macro_rules!` or `#[macro_use]`, it is an ambiguity error.

r? @nrc

1 files changed, 0 insertions, 2 deletions

diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs
index 2dd83f70823..5466c8871d4 100644
--- a/src/librustc_driver/driver.rs
+++ b/src/librustc_driver/driver.rs
@@ -755,8 +755,6 @@ pub fn phase_2_configure_and_expand<'a, F>(sess: &Session,
          || ast_validation::check_crate(sess, &krate));
 
     time(sess.time_passes(), "name resolution", || -> CompileResult {
-        resolver.resolve_imports();
-
         // Since import resolution will eventually happen in expansion,
         // don't perform `after_expand` until after import resolution.
         after_expand(&krate)?;