resolve: Properly integrate derives and macro_rules scopes

src/test/ui/proc-macro/auxiliary/gen-macro-rules.rs

@@ -0,0 +1,12 @@
+// force-host
+// no-prefer-dynamic
+
+#![crate_type = "proc-macro"]
+
+extern crate proc_macro;
+use proc_macro::TokenStream;
+
+#[proc_macro_derive(repro)]
+pub fn proc_macro_hack_expr(_input: TokenStream) -> TokenStream {
+    "macro_rules! m {()=>{}}".parse().unwrap()
+}

src/test/ui/proc-macro/gen-macro-rules.rs

@@ -0,0 +1,13 @@
+// Derive macros can generate `macro_rules` items, regression test for issue #63651.
+
+// check-pass
+// aux-build:gen-macro-rules.rs
+
+extern crate gen_macro_rules as repro;
+
+#[derive(repro::repro)]
+pub struct S;
+
+m!(); // OK
+
+fn main() {}