diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -4141,8 +4141,8 @@
   assert(vecType->isBuiltinType() || vecType->isDependentType() ||
          (vecType->isBitIntType() &&
           // Only support _BitInt elements with byte-sized power of 2 NumBits.
-          llvm::isPowerOf2_32(vecType->getAs<BitIntType>()->getNumBits()) &&
-          vecType->getAs<BitIntType>()->getNumBits() >= 8));
+          llvm::isPowerOf2_32(vecType->castAs<BitIntType>()->getNumBits()) &&
+          vecType->castAs<BitIntType>()->getNumBits() >= 8));
 
   // Check if we've already instantiated a vector of this type.
   llvm::FoldingSetNodeID ID;
diff --git a/clang/lib/Frontend/FrontendActions.cpp b/clang/lib/Frontend/FrontendActions.cpp
--- a/clang/lib/Frontend/FrontendActions.cpp
+++ b/clang/lib/Frontend/FrontendActions.cpp
@@ -458,6 +458,8 @@
       return;
     }
 
+    assert(NamedCtx && "NamedCtx cannot be null");
+
     if (const auto *Decl = dyn_cast<ParmVarDecl>(NamedTemplate)) {
       OS << "unnamed function parameter " << Decl->getFunctionScopeIndex()
          << " ";
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -2790,7 +2790,7 @@
 
   // Only support _BitInt elements with byte-sized power of 2 NumBits.
   if (T->isBitIntType()) {
-    unsigned NumBits = T->getAs<BitIntType>()->getNumBits();
+    unsigned NumBits = T->castAs<BitIntType>()->getNumBits();
     if (!llvm::isPowerOf2_32(NumBits) || NumBits < 8) {
       Diag(AttrLoc, diag::err_attribute_invalid_bitint_vector_type)
           << (NumBits < 8);
diff --git a/clang/lib/StaticAnalyzer/Checkers/CheckObjCDealloc.cpp b/clang/lib/StaticAnalyzer/Checkers/CheckObjCDealloc.cpp
--- a/clang/lib/StaticAnalyzer/Checkers/CheckObjCDealloc.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/CheckObjCDealloc.cpp
@@ -321,7 +321,9 @@
   if (!IvarRegion)
     return nullptr;
 
-  return IvarRegion->getSymbolicBase()->getSymbol();
+  const SymbolicRegion *SR = IvarRegion->getSymbolicBase();
+  assert(SR && "Symbolic base should not be nullptr");
+  return SR->getSymbol();
 }
 
 /// If we are in -dealloc or -dealloc is on the stack, handle the call if it is
diff --git a/clang/lib/StaticAnalyzer/Checkers/PthreadLockChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/PthreadLockChecker.cpp
--- a/clang/lib/StaticAnalyzer/Checkers/PthreadLockChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/PthreadLockChecker.cpp
@@ -291,6 +291,7 @@
   // Existence in DestroyRetVal ensures existence in LockMap.
   // Existence in Destroyed also ensures that the lock state for lockR is either
   // UntouchedAndPossiblyDestroyed or UnlockedAndPossiblyDestroyed.
+  assert(lstate);
   assert(lstate->isUntouchedAndPossiblyDestroyed() ||
          lstate->isUnlockedAndPossiblyDestroyed());