From b4810089ec271f0863d778e64ed30642ba315ee6 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Sat, 9 Nov 2024 23:02:12 +0100
Subject: [PATCH] fix: gcc-12 compilation fixed

Resolves #632
---
 src/core/include/mp-units/framework/expression_template.h | 8 +++++---
 .../include/mp-units/framework/quantity_spec_concepts.h   | 4 ++--
 test/static/custom_rep_test_min_impl.cpp                  | 2 +-
 test/static/si_test.cpp                                   | 3 ++-
 4 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/src/core/include/mp-units/framework/expression_template.h b/src/core/include/mp-units/framework/expression_template.h
index 3448bb33..b0d2138f 100644
--- a/src/core/include/mp-units/framework/expression_template.h
+++ b/src/core/include/mp-units/framework/expression_template.h
@@ -48,9 +48,11 @@ template<typename T>
 concept SymbolicArg = (!std::is_const_v<T>) && (!std::is_reference_v<T>);
 
 template<typename T>
-concept SymbolicConstant =
-  SymbolicArg<T> && std::is_empty_v<T> && std::is_trivial_v<T> && std::semiregular<T> && std::is_final_v<T>;
-
+concept SymbolicConstant = SymbolicArg<T> && std::is_empty_v<T> && std::is_trivial_v<T> &&
+#if !MP_UNITS_COMP_GCC || MP_UNITS_COMP_GCC > 12
+                           std::semiregular<T> &&
+#endif
+                           std::is_final_v<T>;
 
 /**
  * @brief Type list type used by the expression template framework
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 6e7e0934..09260efa 100644
--- a/src/core/include/mp-units/framework/quantity_spec_concepts.h
+++ b/src/core/include/mp-units/framework/quantity_spec_concepts.h
@@ -117,8 +117,8 @@ concept ChildQuantitySpecOf = (is_child_of(Child, Parent));
 
 template<auto To, auto From>
 concept NestedQuantityKindSpecOf =
-  QuantitySpec<decltype(From)> && QuantitySpec<decltype(To)> && (!SameQuantitySpec<get_kind(From), get_kind(To)>) &&
-  ChildQuantitySpecOf<To, get_kind(From)._quantity_spec_>;
+  QuantitySpec<MP_UNITS_REMOVE_CONST(decltype(From))> && QuantitySpec<MP_UNITS_REMOVE_CONST(decltype(To))> &&
+  (!SameQuantitySpec<get_kind(From), get_kind(To)>) && ChildQuantitySpecOf<To, get_kind(From)._quantity_spec_>;
 
 template<auto From, auto To>
 concept QuantitySpecConvertibleTo =
diff --git a/test/static/custom_rep_test_min_impl.cpp b/test/static/custom_rep_test_min_impl.cpp
index 4fb2537b..e2810eaa 100644
--- a/test/static/custom_rep_test_min_impl.cpp
+++ b/test/static/custom_rep_test_min_impl.cpp
@@ -86,7 +86,7 @@ static_assert(!std::convertible_to<min_impl<double>, quantity<si::metre, min_imp
 
 // multiply syntax should work
 template<typename T, auto U>
-concept creates_quantity = Unit<decltype(U)> && requires { T{} * U; };
+concept creates_quantity = Unit<MP_UNITS_REMOVE_CONST(decltype(U))> && requires { T{} * U; };
 
 static_assert(creates_quantity<min_impl<int>, si::metre>);
 static_assert(creates_quantity<min_impl<double>, si::metre>);
diff --git a/test/static/si_test.cpp b/test/static/si_test.cpp
index 4f306fd2..40a9e411 100644
--- a/test/static/si_test.cpp
+++ b/test/static/si_test.cpp
@@ -61,7 +61,8 @@ static_assert(1 * Qm == 1'000'000'000'000'000'000 * Tm);
 
 // check for invalid prefixes
 template<template<typename U> typename prefix, auto V1>
-concept can_not_be_prefixed = Unit<decltype(V1)> && !requires { typename prefix<decltype(V1)>; };
+concept can_not_be_prefixed =
+  Unit<MP_UNITS_REMOVE_CONST(decltype(V1))> && !requires { typename prefix<MP_UNITS_REMOVE_CONST(decltype(V1))>; };
 
 static_assert(can_not_be_prefixed<si::milli_, si::kilogram>);
 static_assert(can_not_be_prefixed<si::milli_, si::hectare>);