[ASTMatchers] add matcher for decltypeType and its underlyingType

Summary:
This patch introduces a new matcher for `DecltypeType` and its underlying type
in order to fix a bug in clang-tidy, see https://reviews.llvm.org/D48717 for more.

Reviewers: aaron.ballman, alexfh, NoQ, dcoughlin

Reviewed By: aaron.ballman

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D48759

llvm-svn: 337703

2 files changed, 2 insertions, 0 deletions

diff --git a/clang/lib/ASTMatchers/ASTMatchersInternal.cpp b/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
index d8af47d7505..0c5902d20c2 100644
--- a/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
+++ b/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
@@ -800,6 +800,7 @@ const AstTypeMatcher<IncompleteArrayType> incompleteArrayType;
 const AstTypeMatcher<VariableArrayType> variableArrayType;
 const AstTypeMatcher<AtomicType> atomicType;
 const AstTypeMatcher<AutoType> autoType;
+const AstTypeMatcher<DecltypeType> decltypeType;
 const AstTypeMatcher<FunctionType> functionType;
 const AstTypeMatcher<FunctionProtoType> functionProtoType;
 const AstTypeMatcher<ParenType> parenType;
diff --git a/clang/lib/ASTMatchers/Dynamic/Registry.cpp b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
index 769d985c054..5a01c5d1f94 100644
--- a/clang/lib/ASTMatchers/Dynamic/Registry.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
@@ -188,6 +188,7 @@ RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(decayedType);
   REGISTER_MATCHER(decl);
   REGISTER_MATCHER(declaratorDecl);
+  REGISTER_MATCHER(decltypeType);
   REGISTER_MATCHER(declCountIs);
   REGISTER_MATCHER(declRefExpr);
   REGISTER_MATCHER(declStmt);