From f17e707edce93fc1a1153879c7800c0a86a52cd6 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Fri, 25 Oct 2024 22:49:58 +0200
Subject: [PATCH] fix: subsumption of `QuantityKindSpec` fixed

---
 src/core/include/mp-units/framework/quantity_spec_concepts.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/core/include/mp-units/framework/quantity_spec_concepts.h b/src/core/include/mp-units/framework/quantity_spec_concepts.h
index d801a7f9..e7d4745f 100644
--- a/src/core/include/mp-units/framework/quantity_spec_concepts.h
+++ b/src/core/include/mp-units/framework/quantity_spec_concepts.h
@@ -53,7 +53,7 @@ struct kind_of_;
 namespace detail {
 
 template<typename T>
-concept QuantityKindSpec = is_specialization_of<T, kind_of_>;
+concept QuantityKindSpec = QuantitySpec<T> && is_specialization_of<T, kind_of_>;
 
 #if MP_UNITS_API_NO_CRTP
 template<auto... Args>