diff --git a/clang-tools-extra/clang-tidy/bugprone/UncheckedOptionalAccessCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/UncheckedOptionalAccessCheck.cpp
--- a/clang-tools-extra/clang-tidy/bugprone/UncheckedOptionalAccessCheck.cpp
+++ b/clang-tools-extra/clang-tidy/bugprone/UncheckedOptionalAccessCheck.cpp
@@ -17,11 +17,12 @@
 #include "clang/Analysis/FlowSensitive/DataflowAnalysisContext.h"
 #include "clang/Analysis/FlowSensitive/DataflowEnvironment.h"
 #include "clang/Analysis/FlowSensitive/DataflowLattice.h"
+#include "clang/Analysis/FlowSensitive/Diagnosis.h"
 #include "clang/Analysis/FlowSensitive/Models/UncheckedOptionalAccessModel.h"
-#include "clang/Analysis/FlowSensitive/SourceLocationsLattice.h"
 #include "clang/Analysis/FlowSensitive/WatchedLiteralsSolver.h"
 #include "clang/Basic/SourceLocation.h"
 #include "llvm/ADT/Any.h"
+#include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/Support/Error.h"
 #include <memory>
@@ -31,16 +32,16 @@
 namespace tidy {
 namespace bugprone {
 using ast_matchers::MatchFinder;
-using dataflow::SourceLocationsLattice;
+using dataflow::UncheckedOptionalAccessDiagnosis;
 using dataflow::UncheckedOptionalAccessModel;
 using llvm::Optional;
 
 static constexpr llvm::StringLiteral FuncID("fun");
 
-static Optional<SourceLocationsLattice>
+static Optional<llvm::DenseSet<SourceLocation>>
 analyzeFunction(const FunctionDecl &FuncDecl, ASTContext &ASTCtx) {
   using dataflow::ControlFlowContext;
-  using dataflow::DataflowAnalysisState;
+  using dataflow::TypeErasedDataflowAnalysisState;
   using llvm::Expected;
 
   Expected<ControlFlowContext> Context =
@@ -52,23 +53,31 @@
       std::make_unique<dataflow::WatchedLiteralsSolver>());
   dataflow::Environment Env(AnalysisContext, FuncDecl);
   UncheckedOptionalAccessModel Analysis(ASTCtx);
-  Expected<std::vector<Optional<DataflowAnalysisState<SourceLocationsLattice>>>>
+  Expected<std::vector<Optional<TypeErasedDataflowAnalysisState>>>
       BlockToOutputState =
-          dataflow::runDataflowAnalysis(*Context, Analysis, Env);
+          dataflow::runTypeErasedDataflowAnalysis(*Context, Analysis, Env);
   if (!BlockToOutputState)
     return llvm::None;
-  assert(Context->getCFG().getExit().getBlockID() < BlockToOutputState->size());
 
-  const Optional<DataflowAnalysisState<SourceLocationsLattice>>
-      &ExitBlockState =
-          (*BlockToOutputState)[Context->getCFG().getExit().getBlockID()];
+  const Optional<TypeErasedDataflowAnalysisState> &ExitBlockState =
+      (*BlockToOutputState)[Context->getCFG().getExit().getBlockID()];
   // `runDataflowAnalysis` doesn't guarantee that the exit block is visited;
   // for example, when it is unreachable.
   // FIXME: Diagnose violations even when the exit block is unreachable.
   if (!ExitBlockState)
     return llvm::None;
 
-  return std::move(ExitBlockState->Lattice);
+  UncheckedOptionalAccessDiagnosis Diagnosis(ASTCtx);
+  dataflow::Diagnosis<UncheckedOptionalAccessModel::Lattice,
+                      llvm::DenseSet<SourceLocation>>
+      Diagnose = [&Diagnosis](const Stmt *Stmt,
+                              const UncheckedOptionalAccessModel::Lattice &,
+                              const dataflow::Environment &Env) {
+        return Diagnosis.diagnose(Stmt, Env);
+      };
+
+  return dataflow::diagnoseCFG(*Context, *BlockToOutputState, Env, Analysis,
+                               std::move(Diagnose));
 }
 
 void UncheckedOptionalAccessCheck::registerMatchers(MatchFinder *Finder) {
@@ -97,9 +106,9 @@
   if (FuncDecl->isTemplated())
     return;
 
-  if (Optional<SourceLocationsLattice> Errors =
+  if (Optional<llvm::DenseSet<SourceLocation>> Errors =
           analyzeFunction(*FuncDecl, *Result.Context))
-    for (const SourceLocation &Loc : Errors->getSourceLocations())
+    for (const SourceLocation &Loc : *Errors)
       diag(Loc, "unchecked access to optional value");
 }