diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 8fb62dd13361f..dd040a3b8896f 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -10030,6 +10030,9 @@ static bool sameObjCTypeArgs(ASTContext &ctx,
     return false;
 
   ObjCTypeParamList *typeParams = iface->getTypeParamList();
+  if (!typeParams)
+    return false;
+
   for (unsigned i = 0, n = lhsArgs.size(); i != n; ++i) {
     if (ctx.hasSameType(lhsArgs[i], rhsArgs[i]))
       continue;
diff --git a/clang/lib/AST/MicrosoftMangle.cpp b/clang/lib/AST/MicrosoftMangle.cpp
index 1f9687e322c9d..9fede7bbad323 100644
--- a/clang/lib/AST/MicrosoftMangle.cpp
+++ b/clang/lib/AST/MicrosoftMangle.cpp
@@ -2689,7 +2689,7 @@ void MicrosoftCXXNameMangler::mangleFunctionType(const FunctionType *T,
         // Copy constructor closure always takes an unqualified reference.
         mangleFunctionArgumentType(getASTContext().getLValueReferenceType(
                                        Proto->getParamType(0)
-                                           ->getAs<LValueReferenceType>()
+                                           ->castAs<LValueReferenceType>()
                                            ->getPointeeType(),
                                        /*SpelledAsLValue=*/true),
                                    Range);
diff --git a/clang/lib/Analysis/ThreadSafety.cpp b/clang/lib/Analysis/ThreadSafety.cpp
index ef7d2cf1ebec2..087994e6ebd70 100644
--- a/clang/lib/Analysis/ThreadSafety.cpp
+++ b/clang/lib/Analysis/ThreadSafety.cpp
@@ -502,9 +502,8 @@ class LocalVariableMap {
     for (Context::iterator I = C.begin(), E = C.end(); I != E; ++I) {
       const NamedDecl *D = I.getKey();
       D->printName(llvm::errs());
-      const unsigned *i = C.lookup(D);
       llvm::errs() << " -> ";
-      dumpVarDefinitionName(*i);
+      dumpVarDefinitionName(I.getData());
       llvm::errs() << "\n";
     }
   }
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index ba5077e873c09..3d9c2b13a243f 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -4955,7 +4955,8 @@ ExprResult Sema::ActOnArraySubscriptExpr(Scope *S, Expr *base,
   };
   // The matrix subscript operator ([][])is considered a single operator.
   // Separating the index expressions by parenthesis is not allowed.
-  if (base->hasPlaceholderType(BuiltinType::IncompleteMatrixIdx) &&
+  if (base && !base->getType().isNull() &&
+      base->hasPlaceholderType(BuiltinType::IncompleteMatrixIdx) &&
       !isa<MatrixSubscriptExpr>(base)) {
     Diag(base->getExprLoc(), diag::err_matrix_separate_incomplete_index)
         << SourceRange(base->getBeginLoc(), rbLoc);
diff --git a/clang/lib/StaticAnalyzer/Checkers/StreamChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/StreamChecker.cpp
index d2ddb5c06f588..5081ff63102b3 100644
--- a/clang/lib/StaticAnalyzer/Checkers/StreamChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/StreamChecker.cpp
@@ -1204,10 +1204,12 @@ StreamChecker::reportLeaks(const SmallVector<SymbolRef, 2> &LeakedSyms,
     // FIXME: Add a checker option to turn this uniqueing feature off.
     const ExplodedNode *StreamOpenNode = getAcquisitionSite(Err, LeakSym, C);
     assert(StreamOpenNode && "Could not find place of stream opening.");
-    PathDiagnosticLocation LocUsedForUniqueing =
-        PathDiagnosticLocation::createBegin(
-            StreamOpenNode->getStmtForDiagnostics(), C.getSourceManager(),
-            StreamOpenNode->getLocationContext());
+
+    PathDiagnosticLocation LocUsedForUniqueing;
+    if (const Stmt *StreamStmt = StreamOpenNode->getStmtForDiagnostics())
+       LocUsedForUniqueing = PathDiagnosticLocation::createBegin(
+          StreamStmt, C.getSourceManager(),
+          StreamOpenNode->getLocationContext());
 
     std::unique_ptr<PathSensitiveBugReport> R =
         std::make_unique<PathSensitiveBugReport>(