From fafa5399f30f851787af9a409db0852001a8f34b Mon Sep 17 00:00:00 2001
From: MarcoFalke <*~=`'#}+{/-|&$^_@721217.xyz>
Date: Thu, 19 Mar 2026 19:36:03 +0100
Subject: [PATCH] Mark gsl::not_null swap noexcept

---
 include/gsl/pointers     | 4 ++--
 tests/pointers_tests.cpp | 4 ++++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/include/gsl/pointers b/include/gsl/pointers
index d73dc05de..c6a5ae88d 100644
--- a/include/gsl/pointers
+++ b/include/gsl/pointers
@@ -145,14 +145,14 @@ public:
     not_null& operator-=(std::ptrdiff_t) = delete;
     void operator[](std::ptrdiff_t) const = delete;
 
-    void swap(not_null<T>& other) { std::swap(ptr_, other.ptr_); }
+    void swap(not_null<T>& other) noexcept { std::swap(ptr_, other.ptr_); }
 
 private:
     T ptr_;
 };
 
 template <typename T, std::enable_if_t<std::is_move_assignable<T>::value && std::is_move_constructible<T>::value, bool> = true>
-void swap(not_null<T>& a, not_null<T>& b)
+void swap(not_null<T>& a, not_null<T>& b) noexcept
 {
     a.swap(b);
 }
diff --git a/tests/pointers_tests.cpp b/tests/pointers_tests.cpp
index 729cc5f0d..6e72bf7cf 100644
--- a/tests/pointers_tests.cpp
+++ b/tests/pointers_tests.cpp
@@ -43,6 +43,8 @@ TEST(pointers_test, swap)
         gsl::not_null<std::unique_ptr<int>> a(std::make_unique<int>(0));
         gsl::not_null<std::unique_ptr<int>> b(std::make_unique<int>(1));
 
+        static_assert(noexcept(gsl::swap(a, b)), "not null unique_ptr should be noexcept-swappable");
+
         EXPECT_TRUE(*a == 0);
         EXPECT_TRUE(*b == 1);
 
@@ -62,6 +64,8 @@ TEST(pointers_test, swap)
         gsl::strict_not_null<std::unique_ptr<int>> a{std::make_unique<int>(0)};
         gsl::strict_not_null<std::unique_ptr<int>> b{std::make_unique<int>(1)};
 
+        static_assert(noexcept(gsl::swap(a, b)), "strict not null unique_ptr should be noexcept-swappable");
+
         EXPECT_TRUE(*a == 0);
         EXPECT_TRUE(*b == 1);