diff --git a/clang/lib/Sema/BSC/SemaBSCTrait.cpp b/clang/lib/Sema/BSC/SemaBSCTrait.cpp
index 31210494b9c493301fd25c6358daf027be8207e3..be4778e7f7d546168b5cbf1beb509da95af0d63d 100644
--- a/clang/lib/Sema/BSC/SemaBSCTrait.cpp
+++ b/clang/lib/Sema/BSC/SemaBSCTrait.cpp
@@ -371,9 +371,11 @@ static bool IsImplTraitDeclIllegal(Sema &S, QualType TraitQT, QualType &ImplQT,
     QualType TraitQT = FieldIt->getType()->getPointeeType();
     const FunctionProtoType *TraitTy = TraitQT->getAs<FunctionProtoType>();
     BSCMethodDecl *MD = nullptr;
-    DeclContext *DC = // The Type's member functions
-        S.getASTContext()
-            .BSCDeclContextMap[ImplQT.getCanonicalType().getTypePtr()];
+    DeclContext *DC = nullptr;
+    if(S.getASTContext().BSCDeclContextMap.find(ImplQT.getCanonicalType().getTypePtr()) != 
+       S.getASTContext().BSCDeclContextMap.end()){
+      DC = S.getASTContext().BSCDeclContextMap[ImplQT.getCanonicalType().getTypePtr()];
+    }
     if (DC) {
       DeclContext::lookup_result DR = DC->lookup(FunctionID);
       for (NamedDecl *D : DR)
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 10c488b24d5b174a3d8d4421c23fd66641f42f08..12754defd3fe36821b318d785d9596e833458ed5 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -2367,7 +2367,10 @@ bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
   DeclContext *DC = SS.isEmpty() ? CurContext : nullptr;
   #if ENABLE_BSC
   if (!ET.isNull()) {
-    DC = getASTContext().BSCDeclContextMap[ET.getCanonicalType().getTypePtr()];
+    if(getASTContext().BSCDeclContextMap.find(ET.getCanonicalType().getTypePtr()) != 
+       getASTContext().BSCDeclContextMap.end()){
+      DC = getASTContext().BSCDeclContextMap[ET.getCanonicalType().getTypePtr()];
+    }
   }
   #endif
   while (DC) {
diff --git a/clang/lib/Sema/SemaExprMember.cpp b/clang/lib/Sema/SemaExprMember.cpp
index 112c767a1b045705ce2c956ab0bf306f108a69eb..a2d0f27f55a9a78b88bae13ce86a705204a5ccbf 100644
--- a/clang/lib/Sema/SemaExprMember.cpp
+++ b/clang/lib/Sema/SemaExprMember.cpp
@@ -1333,9 +1333,10 @@ Sema::BuildMemberReferenceExpr(Expr *BaseExpr, QualType BaseExprType,
     if (!ET.isNull()) {
       if (const BuiltinType *BTy = ET->getAs<BuiltinType>())
         BuiltinName = BTy->getNameAsCString(getPrintingPolicy());
-      else
-        DC = getASTContext()
-                 .BSCDeclContextMap[ET.getCanonicalType().getTypePtr()];
+      else if(getASTContext().BSCDeclContextMap.find(ET.getCanonicalType().getTypePtr()) != 
+          getASTContext().BSCDeclContextMap.end()){
+          DC = getASTContext().BSCDeclContextMap[ET.getCanonicalType().getTypePtr()];
+      }
       // If this first parameter is not "this",
       // it can only be called through '::'.
       if (!MemberFn->getHasThisParam()) {
@@ -1560,6 +1561,8 @@ static ExprResult LookupMemberExpr(Sema &S, LookupResult &R,
           S.getASTContext().BSCDeclContextMap.end()) {
         auto DeclContext = S.getASTContext().BSCDeclContextMap[BTy];
         // TODO: add assert
+        if(!DeclContext)
+          return ExprResult(TE); 
         RecordDecl *Rdecl = dyn_cast<RecordDecl>(DeclContext);
         const RecordType *RTy = dyn_cast<RecordType>(Rdecl->getTypeForDecl());
         if (LookupMemberExprInRecord(S, R, BaseExpr.get(), RTy, OpLoc, IsArrow,
diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index 624fbb8ea8a31b8b8cdd8012fc02c55dc92cc38c..b7f6ba9761c71b63f28c6a66e3d583ee6b6a99b6 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -2775,8 +2775,11 @@ bool Sema::LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS,
 
 #if ENABLE_BSC
   if (!T.isNull() && getLangOpts().BSC) {
-    DeclContext *DC =
-        getASTContext().BSCDeclContextMap[T.getCanonicalType().getTypePtr()];
+    DeclContext *DC = nullptr;
+    if(getASTContext().BSCDeclContextMap.find(T.getCanonicalType().getTypePtr()) != 
+       getASTContext().BSCDeclContextMap.end()){
+      DC = getASTContext().BSCDeclContextMap[T.getCanonicalType().getTypePtr()];
+    }
     if (DC)
       return LookupQualifiedName(R, DC);
     else
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 018f30cc8063cefb95ad5f51b7dceb3fafcc8bea..25e0c1b7df8956cb1193dd6e9f0a107e36352b43 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -494,8 +494,11 @@ bool Sema::LookupTemplateName(LookupResult &Found,
   }
 #if ENABLE_BSC
   if (!T.isNull() && getLangOpts().BSC) {
-    DeclContext *DC =
-        getASTContext().BSCDeclContextMap[T.getCanonicalType().getTypePtr()];
+    DeclContext *DC = nullptr;
+    if(getASTContext().BSCDeclContextMap.find(T.getCanonicalType().getTypePtr()) != 
+       getASTContext().BSCDeclContextMap.end()){
+      DC = getASTContext().BSCDeclContextMap[T.getCanonicalType().getTypePtr()];
+    }
     if (DC)
       LookupQualifiedName(Found, DC);
   }
@@ -3213,9 +3216,11 @@ TemplateParameterList *Sema::MatchTemplateParametersToScopeSpecifier(
       T = QualType(SS.getScopeRep()->getAsType(), 0);
   #if ENABLE_BSC
   } else if (!ExtendedTy.isNull()) {
-    DeclContext *DC =
-        getASTContext()
-            .BSCDeclContextMap[ExtendedTy.getCanonicalType().getTypePtr()];
+    DeclContext *DC = nullptr;
+    if(getASTContext().BSCDeclContextMap.find(ExtendedTy.getCanonicalType().getTypePtr()) != 
+       getASTContext().BSCDeclContextMap.end()){
+      DC = getASTContext().BSCDeclContextMap[ExtendedTy.getCanonicalType().getTypePtr()];
+    }
     if (DC) {
       if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(DC))
         T = Context.getTypeDeclType(Record);
diff --git a/clang/test/BSC/Negative/Method/BuiltInType/void_member_call/void_member_call.cbs b/clang/test/BSC/Negative/Method/BuiltInType/void_member_call/void_member_call.cbs
new file mode 100644
index 0000000000000000000000000000000000000000..75ec1bc9301c12b40e42a9213d98d2eebeff8bcf
--- /dev/null
+++ b/clang/test/BSC/Negative/Method/BuiltInType/void_member_call/void_member_call.cbs
@@ -0,0 +1,43 @@
+// RUN: %clang_cc1 -verify %s
+
+void * func1() {
+    void::memvar; // expected-error{{variable has incomplete type 'void'}} expected-error{{use of undeclared identifier 'memvar'}}
+    void *ptr;
+    ptr->var; // expected-error{{no member named 'var' in type 'void'}}
+}
+
+
+void * func2() {
+    void *ptr;
+    ptr->var;  // expected-error{{no member named 'var' in type 'void'}}
+}
+
+void * func3() {
+    void::memfunc();  // expected-error{{variable has incomplete type 'void'}} expected-error{{use of undeclared identifier 'memfunc'}}
+    void *ptr;
+    ptr->var;  // expected-error{{no member named 'var' in type 'void'}}
+}
+
+void void::memfunc_defined(){  // expected-error{{variable has incomplete type 'void'}}
+    return;
+}
+void * func4() {
+    void::memfunc_defined();  // expected-error{{variable has incomplete type 'void'}} expected-error{{use of undeclared identifier 'memfunc_defined'}}
+    void *ptr;
+    ptr->var;  // expected-error{{no member named 'var' in type 'void'}}
+}
+
+void int::memfunc_defined(){
+    return;
+}
+void * func5() {
+    int::memfunc_defined();
+    int *ptr;
+    ptr->var;  // expected-error{{no member named 'var' in type 'int'}}
+}
+
+void * func6() {
+    void int::var;  // expected-error{{cannot combine with previous 'void' declaration specifier}} expected-error{{variable has incomplete type 'void'}} expected-error{{use of undeclared identifier 'var'}}
+    void *ptr;
+    ptr->var;  // expected-error{{no member named 'var' in type 'void'}}
+}
\ No newline at end of file