2 files changed, 48 insertions, 7 deletions
diff --git a/clang/lib/ASTMatchers/ASTMatchersInternal.cpp b/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
index e501ee64f7e..b95004a6d43 100644
--- a/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
+++ b/clang/lib/ASTMatchers/ASTMatchersInternal.cpp
@@ -26,6 +26,17 @@ void BoundNodesTreeBuilder::visitMatches(Visitor *ResultVisitor) {
   }
 }
 
+bool DynTypedMatcher::canConvertTo(ast_type_traits::ASTNodeKind To) const {
+  const auto From = getSupportedKind();
+  auto QualKind = ast_type_traits::ASTNodeKind::getFromNodeKind<QualType>();
+  auto TypeKind = ast_type_traits::ASTNodeKind::getFromNodeKind<Type>();
+  /// Mimic the implicit conversions of Matcher<>.
+  /// - From Matcher<Type> to Matcher<QualType>
+  if (From.isSame(TypeKind) && To.isSame(QualKind)) return true;
+  /// - From Matcher<Base> to Matcher<Derived>
+  return From.isBaseOf(To);
+}
+
 DynTypedMatcher::MatcherStorage::~MatcherStorage() {}
 
 void BoundNodesTreeBuilder::addMatch(const BoundNodesTreeBuilder &Other) {
diff --git a/clang/lib/ASTMatchers/Dynamic/VariantValue.cpp b/clang/lib/ASTMatchers/Dynamic/VariantValue.cpp
index 57c7b80d361..3d14157fcab 100644
--- a/clang/lib/ASTMatchers/Dynamic/VariantValue.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/VariantValue.cpp
@@ -49,7 +49,32 @@ bool ArgKind::isConvertibleTo(ArgKind To, unsigned *Specificity) const {
   return true;
 }
 
-VariantMatcher::MatcherOps::~MatcherOps() {}
+bool
+VariantMatcher::MatcherOps::canConstructFrom(const DynTypedMatcher &Matcher,
+                                             bool &IsExactMatch) const {
+  IsExactMatch = Matcher.getSupportedKind().isSame(NodeKind);
+  return Matcher.canConvertTo(NodeKind);
+}
+
+llvm::Optional<DynTypedMatcher>
+VariantMatcher::MatcherOps::constructVariadicOperator(
+    ast_matchers::internal::VariadicOperatorFunction Func,
+    ArrayRef<VariantMatcher> InnerMatchers) const {
+  std::vector<DynTypedMatcher> DynMatchers;
+  for (const auto &InnerMatcher : InnerMatchers) {
+    // Abort if any of the inner matchers can't be converted to
+    // Matcher<T>.
+    if (!InnerMatcher.Value)
+      return llvm::None;
+    llvm::Optional<DynTypedMatcher> Inner =
+        InnerMatcher.Value->getTypedMatcher(*this);
+    if (!Inner)
+      return llvm::None;
+    DynMatchers.push_back(*Inner);
+  }
+  return DynTypedMatcher::constructVariadic(Func, DynMatchers);
+}
+
 VariantMatcher::Payload::~Payload() {}
 
 class VariantMatcher::SinglePayload : public VariantMatcher::Payload {
@@ -65,10 +90,12 @@ public:
         .str();
   }
 
-  void makeTypedMatcher(MatcherOps &Ops) const override {
+  llvm::Optional<DynTypedMatcher>
+  getTypedMatcher(const MatcherOps &Ops) const override {
     bool Ignore;
     if (Ops.canConstructFrom(Matcher, Ignore))
-      Ops.constructFrom(Matcher);
+      return Matcher;
+    return llvm::None;
   }
 
   bool isConvertibleTo(ast_type_traits::ASTNodeKind Kind,
@@ -104,7 +131,8 @@ public:
     return (Twine("Matcher<") + Inner + ">").str();
   }
 
-  void makeTypedMatcher(MatcherOps &Ops) const override {
+  llvm::Optional<DynTypedMatcher>
+  getTypedMatcher(const MatcherOps &Ops) const override {
     bool FoundIsExact = false;
     const DynTypedMatcher *Found = nullptr;
     int NumFound = 0;
@@ -124,7 +152,8 @@ public:
     }
     // We only succeed if we found exactly one, or if we found an exact match.
     if (Found && (FoundIsExact || NumFound == 1))
-      Ops.constructFrom(*Found);
+      return *Found;
+    return llvm::None;
   }
 
   bool isConvertibleTo(ast_type_traits::ASTNodeKind Kind,
@@ -165,8 +194,9 @@ public:
     return Inner;
   }
 
-  void makeTypedMatcher(MatcherOps &Ops) const override {
-    Ops.constructVariadicOperator(Func, Args);
+  llvm::Optional<DynTypedMatcher>
+  getTypedMatcher(const MatcherOps &Ops) const override {
+    return Ops.constructVariadicOperator(Func, Args);
   }
 
   bool isConvertibleTo(ast_type_traits::ASTNodeKind Kind,