diff --git a/libcxxabi/test/test_demangle.pass.cpp b/libcxxabi/test/test_demangle.pass.cpp
--- a/libcxxabi/test/test_demangle.pass.cpp
+++ b/libcxxabi/test/test_demangle.pass.cpp
@@ -644,6 +644,7 @@
     {"_ZNSs4_Rep20_S_empty_rep_storageE", "std::string::_Rep::_S_empty_rep_storage"},
     {"_ZZN23ImageLoaderMachOClassic26bindIndirectSymbolPointersERKN11ImageLoader11LinkContextEbbE13alreadyWarned", "ImageLoaderMachOClassic::bindIndirectSymbolPointers(ImageLoader::LinkContext const&, bool, bool)::alreadyWarned"},
     {"_ZN12_GLOBAL__N_115emergency_mutexE", "(anonymous namespace)::emergency_mutex"},
+    {"_Z1fIDnLDn0EEvv", "void f<std::nullptr_t, (std::nullptr_t)0>()"},
 
     // clang
 
diff --git a/llvm/include/llvm/Demangle/ItaniumDemangle.h b/llvm/include/llvm/Demangle/ItaniumDemangle.h
--- a/llvm/include/llvm/Demangle/ItaniumDemangle.h
+++ b/llvm/include/llvm/Demangle/ItaniumDemangle.h
@@ -4342,6 +4342,10 @@
   case 'D':
     if (consumeIf("DnE"))
       return make<NameType>("nullptr");
+    // A template argument which happens to be a null pointer is mangled as if
+    // it were a literal 0 of the appropriate pointer type.
+    if (consumeIf("Dn0E"))
+      return make<EnumLiteral>(make<NameType>("std::nullptr_t"), "0");
     return nullptr;
   case 'T':
     // Invalid mangled name per