diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -292,6 +292,9 @@
 
 Windows Support
 ^^^^^^^^^^^^^^^
+- Fixed an assertion failure that occurred due to a failure to propagate
+  ``MSInheritanceAttr`` attributes to class template instantiations created
+  for explicit template instantiation declarations.
 
 LoongArch Support
 ^^^^^^^^^^^^^^^^^
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -10110,6 +10110,17 @@
         ClassTemplate, CanonicalConverted, PrevDecl);
     SetNestedNameSpecifier(*this, Specialization, SS);
 
+    // A MSInheritanceAttr attached to the previous declaration must be
+    // propagated to the new node prior to instantiation.
+    if (PrevDecl) {
+      if (const auto *A = PrevDecl->getAttr<MSInheritanceAttr>()) {
+        auto *Clone = A->clone(getASTContext());
+        Clone->setInherited(true);
+        Specialization->addAttr(Clone);
+        Consumer.AssignInheritanceModel(Specialization);
+      }
+    }
+
     if (!HasNoEffect && !PrevDecl) {
       // Insert the new specialization.
       ClassTemplate->AddSpecialization(Specialization, InsertPos);
@@ -10226,11 +10237,6 @@
       dllExportImportClassTemplateSpecialization(*this, Def);
     }
 
-    if (Def->hasAttr<MSInheritanceAttr>()) {
-      Specialization->addAttr(Def->getAttr<MSInheritanceAttr>());
-      Consumer.AssignInheritanceModel(Specialization);
-    }
-
     // Set the template specialization kind. Make sure it is set before
     // instantiating the members which will trigger ASTConsumer callbacks.
     Specialization->setTemplateSpecializationKind(TSK);
diff --git a/clang/test/CodeGenCXX/microsoft-abi-member-pointers.cpp b/clang/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
--- a/clang/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
+++ b/clang/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
@@ -1,5 +1,6 @@
 // RUN: %clang_cc1 -std=c++11 -Wno-uninitialized -fno-rtti -emit-llvm %s -o - -triple=i386-pc-win32 -fms-extensions | FileCheck -allow-deprecated-dag-overlap %s
 // RUN: %clang_cc1 -std=c++11 -Wno-uninitialized -fno-rtti -emit-llvm %s -o - -triple=x86_64-pc-win32 -fms-extensions | FileCheck %s -check-prefix=X64
+// RUN: %clang_cc1 -std=c++17 -Wno-uninitialized -fno-rtti -emit-llvm %s -o - -triple=x86_64-pc-win32 -fms-extensions | FileCheck %s -check-prefix=X64
 // RUN: %clang_cc1 -std=c++11 -Wno-uninitialized -fno-rtti -emit-llvm %s -o - -triple=i386-pc-win32 -DINCOMPLETE_VIRTUAL -fms-extensions -verify
 // RUN: %clang_cc1 -std=c++11 -Wno-uninitialized -fno-rtti -emit-llvm %s -o - -triple=i386-pc-win32 -DINCOMPLETE_VIRTUAL -DMEMFUN -fms-extensions -verify
 
@@ -934,3 +935,32 @@
 void A::printd() { JSMethod<A, &A::printd>(); }
 // CHECK-LABEL: @"??$JSMethod@VA@PMFInTemplateArgument@@$1?printd@12@AAEHH@Z@PMFInTemplateArgument@@YAXXZ"(
 }
+
+namespace MissingMSInheritanceAttr {
+// This is a regression test for an assertion failure that occurred when
+// compiling for C++17. The issue concerned a failure to propagate a
+// MSInheritanceAttr attribute for the explicit template instantiation
+// definition prior to it being required to complete the specialization
+// definition in order to determine its alignment so as to resolve a
+// lookup for a deallocation function for the virtual destructor.
+template <typename>
+class a;
+struct b {
+  typedef void (a<int>::*f)();
+  f d;
+};
+template <typename>
+class a {
+  virtual ~a();
+  b e;
+};
+extern template class a<int>;
+template class a<int>;
+#ifdef _WIN64
+static_assert(sizeof(b::d) == 24, "");
+static_assert(sizeof(void (a<int>::*)()) == 24, "");
+#else
+static_assert(sizeof(b::d) == 16, "");
+static_assert(sizeof(void (a<int>::*)()) == 16, "");
+#endif
+}