diff --git a/devel/catch/files/patch-clang21 b/devel/catch/files/patch-clang21
new file mode 100644
index 000000000000..ecaf1667a42c
--- /dev/null
+++ b/devel/catch/files/patch-clang21
@@ -0,0 +1,73 @@
+--- include/internal/catch_approx.cpp.orig	2022-10-16 09:02:17 UTC
++++ include/internal/catch_approx.cpp
+@@ -73,10 +73,10 @@ namespace literals {
+ } // end namespace Detail
+ 
+ namespace literals {
+-    Detail::Approx operator "" _a(long double val) {
++    Detail::Approx operator ""_a(long double val) {
+         return Detail::Approx(val);
+     }
+-    Detail::Approx operator "" _a(unsigned long long val) {
++    Detail::Approx operator ""_a(unsigned long long val) {
+         return Detail::Approx(val);
+     }
+ } // end namespace literals
+--- include/internal/catch_approx.h.orig	2022-10-16 09:02:17 UTC
++++ include/internal/catch_approx.h
+@@ -118,8 +118,8 @@ namespace literals {
+ } // end namespace Detail
+ 
+ namespace literals {
+-    Detail::Approx operator "" _a(long double val);
+-    Detail::Approx operator "" _a(unsigned long long val);
++    Detail::Approx operator ""_a(long double val);
++    Detail::Approx operator ""_a(unsigned long long val);
+ } // end namespace literals
+ 
+ template<>
+--- include/internal/catch_stringref.h.orig	2022-10-16 09:02:17 UTC
++++ include/internal/catch_stringref.h
+@@ -92,12 +92,12 @@ namespace Catch {
+     auto operator << ( std::ostream& os, StringRef const& sr ) -> std::ostream&;
+ 
+ 
+-    constexpr auto operator "" _sr( char const* rawChars, std::size_t size ) noexcept -> StringRef {
++    constexpr auto operator ""_sr( char const* rawChars, std::size_t size ) noexcept -> StringRef {
+         return StringRef( rawChars, size );
+     }
+ } // namespace Catch
+ 
+-constexpr auto operator "" _catch_sr( char const* rawChars, std::size_t size ) noexcept -> Catch::StringRef {
++constexpr auto operator ""_catch_sr( char const* rawChars, std::size_t size ) noexcept -> Catch::StringRef {
+     return Catch::StringRef( rawChars, size );
+ }
+ 
+--- projects/SelfTest/IntrospectiveTests/String.tests.cpp.orig	2022-10-16 09:02:17 UTC
++++ projects/SelfTest/IntrospectiveTests/String.tests.cpp
+@@ -141,7 +141,7 @@ TEST_CASE("StringRef at compilation time", "[Strings][
+         STATIC_REQUIRE(sr1.size() == 3);
+         STATIC_REQUIRE(sr1.isNullTerminated());
+ 
+-        using Catch::operator"" _sr;
++        using Catch::operator""_sr;
+         constexpr auto sr2 = ""_sr;
+         STATIC_REQUIRE(sr2.empty());
+         STATIC_REQUIRE(sr2.size() == 0);
+--- projects/SelfTest/UsageTests/ToStringVariant.tests.cpp.orig	2022-10-16 09:02:17 UTC
++++ projects/SelfTest/UsageTests/ToStringVariant.tests.cpp
+@@ -10,12 +10,12 @@ struct MyType1 {
+ struct MyType1 {
+     MyType1() = default;
+     [[noreturn]] MyType1(MyType1 const&) { throw 1; }
+-    MyType1& operator=(MyType1 const&) { throw 3; }
++    [[noreturn]] MyType1& operator=(MyType1 const&) { throw 3; }
+ };
+ struct MyType2 {
+     MyType2() = default;
+     [[noreturn]] MyType2(MyType2 const&) { throw 2; }
+-    MyType2& operator=(MyType2 const&) { throw 4; }
++    [[noreturn]] MyType2& operator=(MyType2 const&) { throw 4; }
+ };
+ 
+ TEST_CASE( "variant<std::monostate>", "[toString][variant][approvals]")
diff --git a/devel/catch/files/patch-include_internal_catch__approx.cpp b/devel/catch/files/patch-include_internal_catch__approx.cpp
deleted file mode 100644
index a552a75312a2..000000000000
--- a/devel/catch/files/patch-include_internal_catch__approx.cpp
+++ /dev/null
@@ -1,15 +0,0 @@
---- include/internal/catch_approx.cpp.orig	2022-10-16 09:02:17 UTC
-+++ include/internal/catch_approx.cpp
-@@ -73,10 +73,10 @@ namespace literals {
- } // end namespace Detail
- 
- namespace literals {
--    Detail::Approx operator "" _a(long double val) {
-+    Detail::Approx operator ""_a(long double val) {
-         return Detail::Approx(val);
-     }
--    Detail::Approx operator "" _a(unsigned long long val) {
-+    Detail::Approx operator ""_a(unsigned long long val) {
-         return Detail::Approx(val);
-     }
- } // end namespace literals
diff --git a/devel/catch/files/patch-include_internal_catch__approx.h b/devel/catch/files/patch-include_internal_catch__approx.h
deleted file mode 100644
index 4ac587fd402d..000000000000
--- a/devel/catch/files/patch-include_internal_catch__approx.h
+++ /dev/null
@@ -1,13 +0,0 @@
---- include/internal/catch_approx.h.orig	2022-10-16 09:02:17 UTC
-+++ include/internal/catch_approx.h
-@@ -118,8 +118,8 @@ namespace literals {
- } // end namespace Detail
- 
- namespace literals {
--    Detail::Approx operator "" _a(long double val);
--    Detail::Approx operator "" _a(unsigned long long val);
-+    Detail::Approx operator ""_a(long double val);
-+    Detail::Approx operator ""_a(unsigned long long val);
- } // end namespace literals
- 
- template<>
diff --git a/devel/catch/files/patch-include_internal_catch__stringref.h b/devel/catch/files/patch-include_internal_catch__stringref.h
deleted file mode 100644
index cf80b6057a02..000000000000
--- a/devel/catch/files/patch-include_internal_catch__stringref.h
+++ /dev/null
@@ -1,17 +0,0 @@
---- include/internal/catch_stringref.h.orig	2022-10-16 09:02:17 UTC
-+++ include/internal/catch_stringref.h
-@@ -92,12 +92,12 @@ namespace Catch {
-     auto operator << ( std::ostream& os, StringRef const& sr ) -> std::ostream&;
- 
- 
--    constexpr auto operator "" _sr( char const* rawChars, std::size_t size ) noexcept -> StringRef {
-+    constexpr auto operator ""_sr( char const* rawChars, std::size_t size ) noexcept -> StringRef {
-         return StringRef( rawChars, size );
-     }
- } // namespace Catch
- 
--constexpr auto operator "" _catch_sr( char const* rawChars, std::size_t size ) noexcept -> Catch::StringRef {
-+constexpr auto operator ""_catch_sr( char const* rawChars, std::size_t size ) noexcept -> Catch::StringRef {
-     return Catch::StringRef( rawChars, size );
- }
- 
diff --git a/devel/catch/files/patch-projects_SelfTest_IntrospectiveTests_String.tests.cpp b/devel/catch/files/patch-projects_SelfTest_IntrospectiveTests_String.tests.cpp
deleted file mode 100644
index 34e1af72ce42..000000000000
--- a/devel/catch/files/patch-projects_SelfTest_IntrospectiveTests_String.tests.cpp
+++ /dev/null
@@ -1,11 +0,0 @@
---- projects/SelfTest/IntrospectiveTests/String.tests.cpp.orig	2022-10-16 09:02:17 UTC
-+++ projects/SelfTest/IntrospectiveTests/String.tests.cpp
-@@ -141,7 +141,7 @@ TEST_CASE("StringRef at compilation time", "[Strings][
-         STATIC_REQUIRE(sr1.size() == 3);
-         STATIC_REQUIRE(sr1.isNullTerminated());
- 
--        using Catch::operator"" _sr;
-+        using Catch::operator""_sr;
-         constexpr auto sr2 = ""_sr;
-         STATIC_REQUIRE(sr2.empty());
-         STATIC_REQUIRE(sr2.size() == 0);
diff --git a/devel/catch/files/patch-projects_SelfTest_UsageTests_ToStringVariant.tests.cpp b/devel/catch/files/patch-projects_SelfTest_UsageTests_ToStringVariant.tests.cpp
deleted file mode 100644
index 7da71b26f779..000000000000
--- a/devel/catch/files/patch-projects_SelfTest_UsageTests_ToStringVariant.tests.cpp
+++ /dev/null
@@ -1,17 +0,0 @@
---- projects/SelfTest/UsageTests/ToStringVariant.tests.cpp.orig	2022-10-16 09:02:17 UTC
-+++ projects/SelfTest/UsageTests/ToStringVariant.tests.cpp
-@@ -10,12 +10,12 @@ struct MyType1 {
- struct MyType1 {
-     MyType1() = default;
-     [[noreturn]] MyType1(MyType1 const&) { throw 1; }
--    MyType1& operator=(MyType1 const&) { throw 3; }
-+    [[noreturn]] MyType1& operator=(MyType1 const&) { throw 3; }
- };
- struct MyType2 {
-     MyType2() = default;
-     [[noreturn]] MyType2(MyType2 const&) { throw 2; }
--    MyType2& operator=(MyType2 const&) { throw 4; }
-+    [[noreturn]] MyType2& operator=(MyType2 const&) { throw 4; }
- };
- 
- TEST_CASE( "variant<std::monostate>", "[toString][variant][approvals]")