diff --git a/clang/lib/AST/MicrosoftMangle.cpp b/clang/lib/AST/MicrosoftMangle.cpp
index dbc161347025c..c177e3b1d01dd 100644
--- a/clang/lib/AST/MicrosoftMangle.cpp
+++ b/clang/lib/AST/MicrosoftMangle.cpp
@@ -3374,7 +3374,15 @@ void MicrosoftCXXNameMangler::mangleType(const MemberPointerType *T,
 
 void MicrosoftCXXNameMangler::mangleType(const TemplateTypeParmType *T,
                                          Qualifiers, SourceRange Range) {
-  Error(Range.getBegin(), "template type parameter type") << Range;
+  Out << '?';
+
+  llvm::SmallString<64> Name;
+  Name += "<TTPT_";
+  Name += llvm::utostr(T->getDepth());
+  Name += "_";
+  Name += llvm::utostr(T->getIndex());
+  Name += ">";
+  mangleSourceName(Name);
 }
 
 void MicrosoftCXXNameMangler::mangleType(const SubstTemplateTypeParmPackType *T,
diff --git a/clang/test/CodeGenCXX/ms-uneval-context-crash.cpp b/clang/test/CodeGenCXX/ms-uneval-context-crash.cpp
new file mode 100644
index 0000000000000..b2f7e58381da8
--- /dev/null
+++ b/clang/test/CodeGenCXX/ms-uneval-context-crash.cpp
@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 -std=c++20 -fms-compatibility -fms-compatibility-version=19.33 -emit-llvm %s -o - -triple=x86_64-windows-msvc | FileCheck %s
+
+template <typename T>
+concept C = requires
+{
+    { T::test([](){}) };
+};
+
+template<typename T>
+struct Widget {};
+
+template <C T>
+struct Widget<T> {};
+
+struct Baz
+{
+    template<typename F>
+    static constexpr decltype(auto) test(F&&) {}
+};
+
+void test()
+{
+    Widget<Baz> w;
+}
+// CHECK: @"?test@@YAXXZ"