From 5aaca8667cbbfa2ae5b72d778796daa3375b46c0 Mon Sep 17 00:00:00 2001
From: klaus triendl <klaus@triendl.eu>
Date: Fri, 17 Nov 2023 18:19:05 +0200
Subject: [PATCH] Fixed constexpr lambda only being available with C++17

---
 dev/functional/config.h            |  6 ++++++
 dev/functional/cxx_core_features.h |  4 ++++
 dev/udf_proxy.h                    |  2 +-
 include/sqlite_orm/sqlite_orm.h    | 12 +++++++++++-
 tests/user_defined_functions.cpp   |  4 ++--
 5 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/dev/functional/config.h b/dev/functional/config.h
index ec984c51d..2c88944ca 100644
--- a/dev/functional/config.h
+++ b/dev/functional/config.h
@@ -6,6 +6,12 @@
 #include <version>
 #endif
 
+#ifdef SQLITE_ORM_CONSTEXPR_LAMBDAS_SUPPORTED
+#define SQLITE_ORM_CONSTEXPR_LAMBDA_CPP17 constexpr
+#else
+#define SQLITE_ORM_CONSTEXPR_LAMBDA_CPP17
+#endif
+
 #ifdef SQLITE_ORM_INLINE_VARIABLES_SUPPORTED
 #define SQLITE_ORM_INLINE_VAR inline
 #else
diff --git a/dev/functional/cxx_core_features.h b/dev/functional/cxx_core_features.h
index d71644fd3..ee804439a 100644
--- a/dev/functional/cxx_core_features.h
+++ b/dev/functional/cxx_core_features.h
@@ -37,6 +37,10 @@
 #define SQLITE_ORM_FOLD_EXPRESSIONS_SUPPORTED
 #endif
 
+#if __cpp_constexpr >= 201603L
+#define SQLITE_ORM_CONSTEXPR_LAMBDAS_SUPPORTED
+#endif
+
 #if __cpp_if_constexpr >= 201606L
 #define SQLITE_ORM_IF_CONSTEXPR_SUPPORTED
 #endif
diff --git a/dev/udf_proxy.h b/dev/udf_proxy.h
index b84431087..7b81d1c2a 100644
--- a/dev/udf_proxy.h
+++ b/dev/udf_proxy.h
@@ -57,7 +57,7 @@ namespace sqlite_orm {
             std::allocator<UDF> allocator;
             using traits = std::allocator_traits<decltype(allocator)>;
 
-            constexpr auto deallocate = [](void* location) noexcept {
+            SQLITE_ORM_CONSTEXPR_LAMBDA_CPP17 auto deallocate = [](void* location) noexcept {
                 std::allocator<UDF> allocator;
                 using traits = std::allocator_traits<decltype(allocator)>;
                 traits::deallocate(allocator, (UDF*)location, 1);
diff --git a/include/sqlite_orm/sqlite_orm.h b/include/sqlite_orm/sqlite_orm.h
index 213aaa13a..e13bbe52c 100644
--- a/include/sqlite_orm/sqlite_orm.h
+++ b/include/sqlite_orm/sqlite_orm.h
@@ -65,6 +65,10 @@ using std::nullptr_t;
 #define SQLITE_ORM_FOLD_EXPRESSIONS_SUPPORTED
 #endif
 
+#if __cpp_constexpr >= 201603L
+#define SQLITE_ORM_CONSTEXPR_LAMBDAS_SUPPORTED
+#endif
+
 #if __cpp_if_constexpr >= 201606L
 #define SQLITE_ORM_IF_CONSTEXPR_SUPPORTED
 #endif
@@ -167,6 +171,12 @@ using std::nullptr_t;
 #include <version>
 #endif
 
+#ifdef SQLITE_ORM_CONSTEXPR_LAMBDAS_SUPPORTED
+#define SQLITE_ORM_CONSTEXPR_LAMBDA_CPP17 constexpr
+#else
+#define SQLITE_ORM_CONSTEXPR_LAMBDA_CPP17
+#endif
+
 #ifdef SQLITE_ORM_INLINE_VARIABLES_SUPPORTED
 #define SQLITE_ORM_INLINE_VAR inline
 #else
@@ -14885,7 +14895,7 @@ namespace sqlite_orm {
             std::allocator<UDF> allocator;
             using traits = std::allocator_traits<decltype(allocator)>;
 
-            constexpr auto deallocate = [](void* location) noexcept {
+            SQLITE_ORM_CONSTEXPR_LAMBDA_CPP17 auto deallocate = [](void* location) noexcept {
                 std::allocator<UDF> allocator;
                 using traits = std::allocator_traits<decltype(allocator)>;
                 traits::deallocate(allocator, (UDF*)location, 1);
diff --git a/tests/user_defined_functions.cpp b/tests/user_defined_functions.cpp
index 0c67031ff..0ac76a3f4 100644
--- a/tests/user_defined_functions.cpp
+++ b/tests/user_defined_functions.cpp
@@ -171,7 +171,7 @@ int FirstFunction::objectsCount = 0;
 int FirstFunction::callsCount = 0;
 
 #if __cpp_aligned_new >= 201606L
-struct alignas(__STDCPP_DEFAULT_NEW_ALIGNMENT__ * 2) OverAlignedScalarFunction {
+struct alignas(2 * __STDCPP_DEFAULT_NEW_ALIGNMENT__) OverAlignedScalarFunction {
     int operator()(int arg) const {
         return arg;
     }
@@ -181,7 +181,7 @@ struct alignas(__STDCPP_DEFAULT_NEW_ALIGNMENT__ * 2) OverAlignedScalarFunction {
     }
 };
 
-struct alignas(__STDCPP_DEFAULT_NEW_ALIGNMENT__ * 2) OverAlignedAggregateFunction {
+struct alignas(2 * __STDCPP_DEFAULT_NEW_ALIGNMENT__) OverAlignedAggregateFunction {
     double sum = 0;
 
     void step(double arg) {