From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id A57C23885C33; Wed, 3 Aug 2022 13:47:03 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org A57C23885C33 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jonathan Wakely To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc r12-8657] libstdc++: Support constexpr global std::string for size < 15 [PR105995] X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/heads/releases/gcc-12 X-Git-Oldrev: 2fd16b1c0269e24fc11b0abd188d006d4d9134c2 X-Git-Newrev: e562236851e06091256593aa0d3fbda60a28e45b Message-Id: <20220803134703.A57C23885C33@sourceware.org> Date: Wed, 3 Aug 2022 13:47:03 +0000 (GMT) X-BeenThere: libstdc++-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libstdc++-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 03 Aug 2022 13:47:03 -0000 https://gcc.gnu.org/g:e562236851e06091256593aa0d3fbda60a28e45b commit r12-8657-ge562236851e06091256593aa0d3fbda60a28e45b Author: Jonathan Wakely Date: Thu Jun 16 14:57:32 2022 +0100 libstdc++: Support constexpr global std::string for size < 15 [PR105995] I don't think this is required by the standard, but it's easy to support. libstdc++-v3/ChangeLog: PR libstdc++/105995 * include/bits/basic_string.h (_M_use_local_data): Initialize the entire SSO buffer. * testsuite/21_strings/basic_string/cons/char/105995.cc: New test. (cherry picked from commit 98a0d72a610a87e8e383d366e50253ddcc9a51dd) Diff: --- libstdc++-v3/include/bits/basic_string.h | 3 ++- .../testsuite/21_strings/basic_string/cons/char/105995.cc | 11 +++++++++++ 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/libstdc++-v3/include/bits/basic_string.h b/libstdc++-v3/include/bits/basic_string.h index 6041d05815b..9777deaf2e9 100644 --- a/libstdc++-v3/include/bits/basic_string.h +++ b/libstdc++-v3/include/bits/basic_string.h @@ -352,7 +352,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 { #if __cpp_lib_is_constant_evaluated if (std::is_constant_evaluated()) - _M_local_buf[0] = _CharT(); + for (_CharT& __c : _M_local_buf) + __c = _CharT(); #endif return _M_local_data(); } diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/cons/char/105995.cc b/libstdc++-v3/testsuite/21_strings/basic_string/cons/char/105995.cc new file mode 100644 index 00000000000..4764ceff72a --- /dev/null +++ b/libstdc++-v3/testsuite/21_strings/basic_string/cons/char/105995.cc @@ -0,0 +1,11 @@ +// { dg-options "-std=gnu++20" } +// { dg-do compile { target c++20 } } +// { dg-require-effective-target cxx11_abi } + +#include + +// PR libstdc++/105995 +// Not required by the standard, but supported for QoI. +constexpr std::string pr105995_empty; +constexpr std::string pr105995_partial = "0"; +constexpr std::string pr105995_full = "0123456789abcde";