Auto merge of #42334 - est31:master, r=jseyfried

Extend the unused macro lint to macros 2.0

Extends the unused macro lint (added in PR #41907) to macros 2.0 (added in PR #40847).

r? @jseyfried

3 files changed, 7 insertions, 4 deletions

diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 71dc81c3759..8089fad5f36 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -552,7 +552,9 @@ pub enum SyntaxExtension {
     BuiltinDerive(BuiltinDeriveFn),
 
     /// A declarative macro, e.g. `macro m() {}`.
-    DeclMacro(Box<TTMacroExpander>, Option<Span> /* definition site span */),
+    ///
+    /// The second element is the definition site span.
+    DeclMacro(Box<TTMacroExpander>, Option<(ast::NodeId, Span)>),
 }
 
 impl SyntaxExtension {
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index be077b48111..c91c77719e6 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -472,8 +472,9 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
 
         let marked_tts = noop_fold_tts(mac.node.stream(), &mut Marker(mark));
         let opt_expanded = match *ext {
-            SyntaxExtension::DeclMacro(ref expand, def_site_span) => {
-                if let Err(msg) = validate_and_set_expn_info(def_site_span, false) {
+            SyntaxExtension::DeclMacro(ref expand, def_span) => {
+                if let Err(msg) = validate_and_set_expn_info(def_span.map(|(_, s)| s),
+                                                             false) {
                     self.cx.span_err(path.span, &msg);
                     return kind.dummy(span);
                 }
diff --git a/src/libsyntax/ext/tt/macro_rules.rs b/src/libsyntax/ext/tt/macro_rules.rs
index 15042e529e5..0472a94e0ce 100644
--- a/src/libsyntax/ext/tt/macro_rules.rs
+++ b/src/libsyntax/ext/tt/macro_rules.rs
@@ -266,7 +266,7 @@ pub fn compile(sess: &ParseSess, features: &RefCell<Features>, def: &ast::Item)
         let allow_internal_unstable = attr::contains_name(&def.attrs, "allow_internal_unstable");
         NormalTT(exp, Some((def.id, def.span)), allow_internal_unstable)
     } else {
-        SyntaxExtension::DeclMacro(exp, Some(def.span))
+        SyntaxExtension::DeclMacro(exp, Some((def.id, def.span)))
     }
 }