diff --git a/src/alloy/backend/x64/x64_sequence.inl b/src/alloy/backend/x64/x64_sequence.inl
index c9451fdfe..5013ba4a6 100644
--- a/src/alloy/backend/x64/x64_sequence.inl
+++ b/src/alloy/backend/x64/x64_sequence.inl
@@ -528,7 +528,12 @@ template <typename SEQ, typename T>
 struct SingleSequence : public Sequence<SingleSequence<SEQ, T>, T> {
   typedef Sequence<SingleSequence<SEQ, T>, T> BASE;
   typedef T EmitArgType;
+  // TODO(benvanik): find a way to do this cross-compiler.
+#if XE_COMPILER_MSVC
+  static uint32_t head_key() { return T::key; }
+#else
   static constexpr uint32_t head_key() { return T::key; }
+#endif  // XE_COMPILER_MSVC
   static void Emit(X64Emitter& e, const typename BASE::EmitArgs& _) {
     SEQ::Emit(e, _.i1);
   }
diff --git a/src/poly/platform.h b/src/poly/platform.h
index 05be89e48..c576e6066 100644
--- a/src/poly/platform.h
+++ b/src/poly/platform.h
@@ -144,13 +144,13 @@ XE_CPU:         32BIT | 64BIT | BIGENDIAN | LITTLEENDIAN
 #if XE_COMPILER_MSVC
 // Disable warning C4068: unknown pragma
 #pragma warning(disable : 4068)
-#endif  // MSVC
+#endif  // XE_COMPILER_MSVC
 
 #if XE_COMPILER_MSVC
 #include <intrin.h>
 #else
 #include <x86intrin.h>
-#endif  // MSVC
+#endif  // XE_COMPILER_MSVC
 
 namespace poly {
 
@@ -160,7 +160,7 @@ const size_t max_path = _MAX_PATH;
 #else
 const char path_separator = '/';
 const size_t max_path = 1024;  // PATH_MAX
-#endif  // WIN32
+#endif  // XE_LIKE_WIN32
 
 }  // namespace poly