From b1542341da756013a4a2126cd7628bbc2a8c3ba7 Mon Sep 17 00:00:00 2001
From: QuietMisdreavus <grey@quietmisdreavus.net>
Date: Tue, 22 Jan 2019 15:40:27 -0600
Subject: [PATCH] don't call get_macro on proc-macro stubs

---
 src/librustdoc/passes/collect_intra_doc_links.rs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/librustdoc/passes/collect_intra_doc_links.rs b/src/librustdoc/passes/collect_intra_doc_links.rs
index 3d6096b07ce4..13ad05101e4b 100644
--- a/src/librustdoc/passes/collect_intra_doc_links.rs
+++ b/src/librustdoc/passes/collect_intra_doc_links.rs
@@ -431,8 +431,12 @@ fn macro_resolve(cx: &DocContext, path_str: &str) -> Option<Def> {
     let parent_scope = resolver.dummy_parent_scope();
     if let Ok(def) = resolver.resolve_macro_to_def_inner(&path, MacroKind::Bang,
                                                          &parent_scope, false, false) {
-        if let SyntaxExtension::DeclMacro { .. } = *resolver.get_macro(def) {
-            return Some(def);
+        if let Def::Macro(_, MacroKind::ProcMacroStub) = def {
+            // skip proc-macro stubs, they'll cause `get_macro` to crash
+        } else {
+            if let SyntaxExtension::DeclMacro { .. } = *resolver.get_macro(def) {
+                return Some(def);
+            }
         }
     }
     if let Some(def) = resolver.all_macros.get(&Symbol::intern(path_str)) {