From a204c0ad180b27281985a9fd38b39f328cd1683b Mon Sep 17 00:00:00 2001
From: Daniel Jasper <djasper@google.com>
Date: Wed, 20 Apr 2016 08:58:27 +0000
Subject: [PATCH] clang-tidy: [misc-unused-using-decls] Always use the
 canonical decl to identify things.

This fixes llvm.org/PR27430.

llvm-svn: 266864
---
 clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.cpp   | 8 +++++---
 clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h     | 4 ++--
 clang-tools-extra/test/clang-tidy/misc-unused-using-decls.cpp | 1 +
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.cpp b/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.cpp
index 5d93357..b2aff4d 100644
--- a/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.cpp
+++ b/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.cpp
@@ -30,7 +30,8 @@ void UnusedUsingDeclsCheck::check(const MatchFinder::MatchResult &Result) {
     // than one shadow.
     if (Using->shadow_size() != 1)
       return;
-    const auto* TargetDecl = Using->shadow_begin()->getTargetDecl();
+    const auto *TargetDecl =
+        Using->shadow_begin()->getTargetDecl()->getCanonicalDecl();
 
     // FIXME: Handle other target types.
     if (!isa<RecordDecl>(TargetDecl))
@@ -52,8 +53,9 @@ void UnusedUsingDeclsCheck::check(const MatchFinder::MatchResult &Result) {
   // FIXME: This currently doesn't look at whether the type reference is
   // actually found with the help of the using declaration.
   if (const auto *Used = Result.Nodes.getNodeAs<NamedDecl>("used")) {
-    if (FoundDecls.find(Used) != FoundDecls.end())
-      FoundDecls[Used] = nullptr;
+    auto I = FoundDecls.find(Used->getCanonicalDecl());
+    if (I != FoundDecls.end())
+      I->second = nullptr;
   }
 }
 
diff --git a/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h b/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h
index 9c899e8..dc8fb88 100644
--- a/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h
+++ b/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h
@@ -30,8 +30,8 @@ public:
   void onEndOfTranslationUnit() override;
 
 private:
-  llvm::DenseMap<const NamedDecl*, const UsingDecl*> FoundDecls;
-  llvm::DenseMap<const NamedDecl*, CharSourceRange> FoundRanges;
+  llvm::DenseMap<const Decl*, const UsingDecl*> FoundDecls;
+  llvm::DenseMap<const Decl*, CharSourceRange> FoundRanges;
 };
 
 } // namespace misc
diff --git a/clang-tools-extra/test/clang-tidy/misc-unused-using-decls.cpp b/clang-tools-extra/test/clang-tidy/misc-unused-using-decls.cpp
index 110c1b4..053e65d 100644
--- a/clang-tools-extra/test/clang-tidy/misc-unused-using-decls.cpp
+++ b/clang-tools-extra/test/clang-tidy/misc-unused-using-decls.cpp
@@ -6,6 +6,7 @@ namespace n {
 class A;
 class B;
 class C;
+class D;
 class D { public: static int i; };
 }
 
-- 
2.7.4