From 00ee881811f64f261465b39abd3c9c278be584b6 Mon Sep 17 00:00:00 2001
From: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
Date: Mon, 9 Dec 2024 01:43:27 +0100
Subject: [PATCH] libstdc++: port away from is_trivial in string classes
In preparation for the deprecation of is_trivial (P3247R2), stop using
it from std::string_view. Also, add the same detection to std::string
(described in [strings.general]/2).
libstdc++-v3/ChangeLog:
* include/bits/basic_string.h: Add a static_assert on the
char-like type.
* include/std/string_view: Port away from is_trivial.
Signed-off-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
---
libstdc++-v3/include/bits/basic_string.h | 3 +++
libstdc++-v3/include/std/string_view | 4 +++-
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/libstdc++-v3/include/bits/basic_string.h b/libstdc++-v3/include/bits/basic_string.h
index 17b973c8b45c..8369c24d3ae3 100644
--- a/libstdc++-v3/include/bits/basic_string.h
+++ b/libstdc++-v3/include/bits/basic_string.h
@@ -88,6 +88,9 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
class basic_string
{
#if __cplusplus >= 202002L
+ static_assert(is_trivially_copyable_v<_CharT>
+ && is_trivially_default_constructible_v<_CharT>
+ && is_standard_layout_v<_CharT>);
static_assert(is_same_v<_CharT, typename _Traits::char_type>);
static_assert(is_same_v<_CharT, typename _Alloc::value_type>);
using _Char_alloc_type = _Alloc;
diff --git a/libstdc++-v3/include/std/string_view b/libstdc++-v3/include/std/string_view
index 96350f96b3c0..493edec26dc8 100644
--- a/libstdc++-v3/include/std/string_view
+++ b/libstdc++-v3/include/std/string_view
@@ -108,7 +108,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
class basic_string_view
{
static_assert(!is_array_v<_CharT>);
- static_assert(is_trivial_v<_CharT> && is_standard_layout_v<_CharT>);
+ static_assert(is_trivially_copyable_v<_CharT>
+ && is_trivially_default_constructible_v<_CharT>
+ && is_standard_layout_v<_CharT>);
static_assert(is_same_v<_CharT, typename _Traits::char_type>);
public:
--
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