diff --git a/clang-tools-extra/clangd/ClangdServer.cpp b/clang-tools-extra/clangd/ClangdServer.cpp
--- a/clang-tools-extra/clangd/ClangdServer.cpp
+++ b/clang-tools-extra/clangd/ClangdServer.cpp
@@ -78,6 +78,8 @@
   }
 
   void onMainAST(PathRef Path, ParsedAST &AST, PublishFn Publish) override {
+    WithContextValue ASTCtx(ParsedAST::CurrentASTContext, &AST.getASTContext());
+
     if (FIndex)
       FIndex->updateMain(Path, AST);
 
diff --git a/clang-tools-extra/clangd/FindTarget.cpp b/clang-tools-extra/clangd/FindTarget.cpp
--- a/clang-tools-extra/clangd/FindTarget.cpp
+++ b/clang-tools-extra/clangd/FindTarget.cpp
@@ -8,6 +8,8 @@
 
 #include "FindTarget.h"
 #include "AST.h"
+#include "ParsedAST.h"
+#include "support/Context.h"
 #include "support/Logger.h"
 #include "clang/AST/ASTTypeTraits.h"
 #include "clang/AST/Decl.h"
@@ -98,21 +100,18 @@
 // name (e.g. if it's an operator name), but the caller may not have
 // access to an ASTContext.
 std::vector<const NamedDecl *> getMembersReferencedViaDependentName(
-    const Type *T,
-    llvm::function_ref<DeclarationName(ASTContext &)> NameFactory,
+    const Type *T, DeclarationName Name,
     llvm::function_ref<bool(const NamedDecl *ND)> Filter) {
   if (!T)
     return {};
   if (auto *ET = T->getAs<EnumType>()) {
-    auto Result =
-        ET->getDecl()->lookup(NameFactory(ET->getDecl()->getASTContext()));
+    auto Result = ET->getDecl()->lookup(Name);
     return {Result.begin(), Result.end()};
   }
   if (auto *RD = resolveTypeToRecordDecl(T)) {
     if (!RD->hasDefinition())
       return {};
     RD = RD->getDefinition();
-    DeclarationName Name = NameFactory(RD->getASTContext());
     return RD->lookupDependentName(Name, Filter);
   }
   return {};
@@ -147,9 +146,9 @@
   // smart pointer type.
   auto ArrowOps = getMembersReferencedViaDependentName(
       T,
-      [](ASTContext &Ctx) {
-        return Ctx.DeclarationNames.getCXXOperatorName(OO_Arrow);
-      },
+      Context::current()
+          .getExisting(ParsedAST::CurrentASTContext)
+          ->DeclarationNames.getCXXOperatorName(OO_Arrow),
       NonStaticFilter);
   if (ArrowOps.empty())
     return nullptr;
@@ -194,14 +193,12 @@
         BaseType = resolveExprToType(Base);
       }
     }
-    return getMembersReferencedViaDependentName(
-        BaseType, [ME](ASTContext &) { return ME->getMember(); },
-        NonStaticFilter);
+    return getMembersReferencedViaDependentName(BaseType, ME->getMember(),
+                                                NonStaticFilter);
   }
   if (const auto *RE = dyn_cast<DependentScopeDeclRefExpr>(E)) {
     return getMembersReferencedViaDependentName(
-        RE->getQualifier()->getAsType(),
-        [RE](ASTContext &) { return RE->getDeclName(); }, StaticFilter);
+        RE->getQualifier()->getAsType(), RE->getDeclName(), StaticFilter);
   }
   if (const auto *CE = dyn_cast<CallExpr>(E)) {
     const auto *CalleeType = resolveExprToType(CE->getCallee());
@@ -253,8 +250,7 @@
   case NestedNameSpecifier::Identifier: {
     return resolveDeclsToType(getMembersReferencedViaDependentName(
         resolveNestedNameSpecifierToType(NNS->getPrefix()),
-        [&](const ASTContext &) { return NNS->getAsIdentifier(); },
-        TypeFilter));
+        NNS->getAsIdentifier(), TypeFilter));
   }
   default:
     break;
@@ -380,8 +376,7 @@
     } else if (const UnresolvedUsingValueDecl *UUVD =
                    dyn_cast<UnresolvedUsingValueDecl>(D)) {
       for (const NamedDecl *Target : getMembersReferencedViaDependentName(
-               UUVD->getQualifier()->getAsType(),
-               [UUVD](ASTContext &) { return UUVD->getNameInfo().getName(); },
+               UUVD->getQualifier()->getAsType(), UUVD->getNameInfo().getName(),
                ValueFilter)) {
         add(Target, Flags); // no Underlying as this is a non-renaming alias
       }
@@ -567,8 +562,7 @@
       void VisitDependentNameType(const DependentNameType *DNT) {
         for (const NamedDecl *ND : getMembersReferencedViaDependentName(
                  resolveNestedNameSpecifierToType(DNT->getQualifier()),
-                 [DNT](ASTContext &) { return DNT->getIdentifier(); },
-                 TypeFilter)) {
+                 DNT->getIdentifier(), TypeFilter)) {
           Outer.add(ND, Flags);
         }
       }
@@ -576,8 +570,7 @@
           const DependentTemplateSpecializationType *DTST) {
         for (const NamedDecl *ND : getMembersReferencedViaDependentName(
                  resolveNestedNameSpecifierToType(DTST->getQualifier()),
-                 [DTST](ASTContext &) { return DTST->getIdentifier(); },
-                 TemplateFilter)) {
+                 DTST->getIdentifier(), TemplateFilter)) {
           Outer.add(ND, Flags);
         }
       }
diff --git a/clang-tools-extra/clangd/ParsedAST.h b/clang-tools-extra/clangd/ParsedAST.h
--- a/clang-tools-extra/clangd/ParsedAST.h
+++ b/clang-tools-extra/clangd/ParsedAST.h
@@ -26,6 +26,7 @@
 #include "Headers.h"
 #include "Preamble.h"
 #include "index/CanonicalIncludes.h"
+#include "support/Context.h"
 #include "support/Path.h"
 #include "clang/Frontend/FrontendAction.h"
 #include "clang/Frontend/PrecompiledPreamble.h"
@@ -109,6 +110,10 @@
   /// AST. Might be None if no Preamble is used.
   llvm::Optional<llvm::StringRef> preambleVersion() const;
 
+  /// This context variable makes available the ASTContext of the AST being
+  /// operated on currently.
+  static Key<ASTContext *> CurrentASTContext;
+
 private:
   ParsedAST(llvm::StringRef Version,
             std::shared_ptr<const PreambleData> Preamble,
diff --git a/clang-tools-extra/clangd/ParsedAST.cpp b/clang-tools-extra/clangd/ParsedAST.cpp
--- a/clang-tools-extra/clangd/ParsedAST.cpp
+++ b/clang-tools-extra/clangd/ParsedAST.cpp
@@ -237,6 +237,8 @@
 
 } // namespace
 
+Key<ASTContext *> ParsedAST::CurrentASTContext;
+
 llvm::Optional<ParsedAST>
 ParsedAST::build(llvm::StringRef Filename, const ParseInputs &Inputs,
                  std::unique_ptr<clang::CompilerInvocation> CI,
diff --git a/clang-tools-extra/clangd/TUScheduler.cpp b/clang-tools-extra/clangd/TUScheduler.cpp
--- a/clang-tools-extra/clangd/TUScheduler.cpp
+++ b/clang-tools-extra/clangd/TUScheduler.cpp
@@ -721,6 +721,8 @@
       return Action(error(llvm::errc::invalid_argument, "invalid AST"));
     vlog("ASTWorker running {0} on version {2} of {1}", Name, FileName,
          FileInputs.Version);
+    WithContextValue Ctx(ParsedAST::CurrentASTContext,
+                         &(*AST)->getASTContext());
     Action(InputsAndAST{FileInputs, **AST});
   };
   startTask(Name, std::move(Task), /*UpdateType=*/None, Invalidation);
diff --git a/clang-tools-extra/clangd/unittests/TestTU.h b/clang-tools-extra/clangd/unittests/TestTU.h
--- a/clang-tools-extra/clangd/unittests/TestTU.h
+++ b/clang-tools-extra/clangd/unittests/TestTU.h
@@ -76,6 +76,10 @@
   // to eliminate this option some day.
   bool OverlayRealFileSystemForModules = false;
 
+  // This is used to add the ASTContext of the AST produced by build() to the
+  // clangd Context.
+  mutable std::unique_ptr<WithContextValue> ASTCtx;
+
   // By default, build() will report Error diagnostics as GTest errors.
   // Suppress this behavior by adding an 'error-ok' comment to the code.
   ParsedAST build() const;
diff --git a/clang-tools-extra/clangd/unittests/TestTU.cpp b/clang-tools-extra/clangd/unittests/TestTU.cpp
--- a/clang-tools-extra/clangd/unittests/TestTU.cpp
+++ b/clang-tools-extra/clangd/unittests/TestTU.cpp
@@ -139,6 +139,8 @@
         break; // Just report first error for simplicity.
       }
   }
+  ASTCtx = std::make_unique<WithContextValue>(ParsedAST::CurrentASTContext,
+                                              &AST->getASTContext());
   return std::move(*AST);
 }