Do not emit the advanced diagnostics on macros

compiler/rustc_resolve/src/late/diagnostics.rs

@@ -456,12 +456,14 @@ pub(crate) fn smart_resolve_report_errors(
             }
         }
 
+        let is_macro = base_span.from_expansion() && base_span.desugaring_kind().is_none();
         if !self.type_ascription_suggestion(&mut err, base_span) {
             let mut fallback = false;
             if let (
                 PathSource::Trait(AliasPossibility::Maybe),
                 Some(Res::Def(DefKind::Struct | DefKind::Enum | DefKind::Union, _)),
-            ) = (source, res)
+                false,
+            ) = (source, res, is_macro)
             {
                 if let Some(bounds @ [_, .., _]) = self.diagnostic_metadata.current_trait_object {
                     fallback = true;

src/test/ui/proc-macro/auxiliary/issue-83510.rs

@@ -0,0 +1,19 @@
+// force-host
+// no-prefer-dynamic
+
+#![crate_type = "proc-macro"]
+
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+
+#[proc_macro]
+pub fn dance_like_you_want_to_ice(_: TokenStream) -> TokenStream {
+    r#"
+    impl Foo {
+        type Bar = Box<()> + Baz;
+    }
+    "#
+    .parse()
+    .unwrap()
+}

src/test/ui/proc-macro/issue-83510.rs

@@ -0,0 +1,11 @@
+// aux-build: issue-83510.rs
+
+extern crate issue_83510;
+
+issue_83510::dance_like_you_want_to_ice!();
+//~^ ERROR: cannot find type `Foo` in this scope
+//~| ERROR: expected trait, found struct `Box`
+//~| ERROR: cannot find trait `Baz` in this scope
+//~| ERROR: inherent associated types are unstable
+
+fn main() {}

src/test/ui/proc-macro/issue-83510.stderr

@@ -0,0 +1,38 @@
+error[E0412]: cannot find type `Foo` in this scope
+  --> $DIR/issue-83510.rs:5:1
+   |
+LL | issue_83510::dance_like_you_want_to_ice!();
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
+   |
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0404]: expected trait, found struct `Box`
+  --> $DIR/issue-83510.rs:5:1
+   |
+LL | issue_83510::dance_like_you_want_to_ice!();
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not a trait
+   |
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0405]: cannot find trait `Baz` in this scope
+  --> $DIR/issue-83510.rs:5:1
+   |
+LL | issue_83510::dance_like_you_want_to_ice!();
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope
+   |
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0658]: inherent associated types are unstable
+  --> $DIR/issue-83510.rs:5:1
+   |
+LL | issue_83510::dance_like_you_want_to_ice!();
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #8995 <https://github.com/rust-lang/rust/issues/8995> for more information
+   = help: add `#![feature(inherent_associated_types)]` to the crate attributes to enable
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to 4 previous errors
+
+Some errors have detailed explanations: E0404, E0405, E0412, E0658.
+For more information about an error, try `rustc --explain E0404`.