File chromium-121-avoid-SFINAE-TypeConverter.patch of Package chromium

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File chromium-121-avoid-SFINAE-TypeConverter.patch of Package chromium (Revision 712db94830c1cef6cee06f96b7f06153)

Currently displaying revision 712db94830c1cef6cee06f96b7f06153 , Show latest

diff --git a/base/types/to_address.h.new b/base/types/to_address.h.new
new file mode 100644
index 0000000..ac71b01
--- /dev/null
+++ b/base/types/to_address.h
@@ -0,0 +1,40 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_TYPES_TO_ADDRESS_H_
+#define BASE_TYPES_TO_ADDRESS_H_
+
+#include <memory>
+#include <type_traits>
+
+// SFINAE-compatible wrapper for `std::to_address()`.
+//
+// The standard does not require `std::to_address()` to be SFINAE-compatible
+// when code attempts instantiation with non-pointer-like types, and libstdc++'s
+// implementation hard errors. For the sake of templated code that wants simple,
+// unified handling, Chromium instead uses this wrapper, which provides that
+// guarantee. This allows code to use "`to_address()` would be valid here" as a
+// constraint to detect pointer-like types.
+namespace base {
+
+// Note that calling `std::to_address()` with a function pointer renders the
+// program ill-formed.
+template <typename T>
+  requires(!std::is_function_v<T>)
+constexpr T* to_address(T* p) noexcept {
+  return p;
+}
+
+// These constraints cover the cases where `std::to_address()`'s fancy pointer
+// overload is well-specified.
+template <typename P>
+  requires requires(const P& p) { std::pointer_traits<P>::to_address(p); } ||
+           requires(const P& p) { p.operator->(); }
+constexpr auto to_address(const P& p) noexcept {
+  return std::to_address(p);
+}
+
+}  // namespace base
+
+#endif  // BASE_TYPES_TO_ADDRESS_H_
diff --git a/mojo/public/cpp/bindings/type_converter.h b/mojo/public/cpp/bindings/type_converter.h.new
index 2eddbb0..317245f 100644
--- a/mojo/public/cpp/bindings/type_converter.h
+++ b/mojo/public/cpp/bindings/type_converter.h
@@ -11,6 +11,8 @@
 #include <memory>
 #include <type_traits>
 
+#include "base/types/to_address.h"
+
 namespace mojo {
 
 // NOTE: When possible, please consider using StructTraits / UnionTraits /
@@ -100,11 +102,11 @@ template <typename T, typename U>
 inline T ConvertTo(const U& obj) {
   if constexpr (requires {
                   {
-                    mojo::ConvertTo<T>(std::to_address(obj))
+                    mojo::ConvertTo<T>(base::to_address(obj))
 
                   } -> std::same_as<T>;
                 }) {
-    return mojo::ConvertTo<T>(std::to_address(obj));
+    return mojo::ConvertTo<T>(base::to_address(obj));
   } else {
     return TypeConverter<T, U>::Convert(obj);
   }

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File chromium-121-avoid-SFINAE-TypeConverter.patch of Package chromium (Revision 712db94830c1cef6cee06f96b7f06153)

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