From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2153) id E4C0E3838008; Tue, 10 May 2022 08:25:30 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E4C0E3838008 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jakub Jelinek To: gcc-cvs@gcc.gnu.org Subject: [gcc r10-10698] c++: extern thread_local declarations in constexpr [PR104994] X-Act-Checkin: gcc X-Git-Author: Jakub Jelinek X-Git-Refname: refs/heads/releases/gcc-10 X-Git-Oldrev: 07ab38979126c39563c2c75b8e40cb7ce9b479b3 X-Git-Newrev: 125234a3b78138e22112bb3f207df987817b6818 Message-Id: <20220510082530.E4C0E3838008@sourceware.org> Date: Tue, 10 May 2022 08:25:30 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 10 May 2022 08:25:31 -0000 https://gcc.gnu.org/g:125234a3b78138e22112bb3f207df987817b6818 commit r10-10698-g125234a3b78138e22112bb3f207df987817b6818 Author: Jakub Jelinek Date: Thu Mar 24 10:12:25 2022 +0100 c++: extern thread_local declarations in constexpr [PR104994] C++14 to C++20 apparently should allow extern thread_local declarations in constexpr functions, however useless they are there (because accessing such vars is not valid in a constant expression, perhaps sizeof/decltype). P2242 changed that for C++23 to passing through declaration but https://cplusplus.github.io/CWG/issues/2552.html has been filed for it yesterday. 2022-03-24 Jakub Jelinek PR c++/104994 * constexpr.c (potential_constant_expression_1): Don't diagnose extern thread_local declarations. * decl.c (start_decl): Likewise. * g++.dg/cpp2a/constexpr-nonlit7.C: New test. (cherry picked from commit 72124f487ccb5c8065dd5f7b8fba254600b7e611) Diff: --- gcc/cp/constexpr.c | 8 ++++---- gcc/cp/decl.c | 2 +- gcc/testsuite/g++.dg/cpp2a/constexpr-nonlit7.C | 6 ++++++ 3 files changed, 11 insertions(+), 5 deletions(-) diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c index 8e193edeff8..dd0e955ed7b 100644 --- a/gcc/cp/constexpr.c +++ b/gcc/cp/constexpr.c @@ -8297,18 +8297,18 @@ potential_constant_expression_1 (tree t, bool want_rval, bool strict, bool now, tmp = DECL_EXPR_DECL (t); if (VAR_P (tmp) && !DECL_ARTIFICIAL (tmp)) { - if (TREE_STATIC (tmp)) + if (CP_DECL_THREAD_LOCAL_P (tmp) && !DECL_REALLY_EXTERN (tmp)) { if (flags & tf_error) error_at (DECL_SOURCE_LOCATION (tmp), "%qD declared " - "% in % context", tmp); + "% in % context", tmp); return false; } - else if (CP_DECL_THREAD_LOCAL_P (tmp)) + else if (TREE_STATIC (tmp)) { if (flags & tf_error) error_at (DECL_SOURCE_LOCATION (tmp), "%qD declared " - "% in % context", tmp); + "% in % context", tmp); return false; } else if (!check_for_uninitialized_const_var diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c index 47dc43177ef..e923fb0fe13 100644 --- a/gcc/cp/decl.c +++ b/gcc/cp/decl.c @@ -5447,7 +5447,7 @@ start_decl (const cp_declarator *declarator, && DECL_DECLARED_CONSTEXPR_P (current_function_decl)) { bool ok = false; - if (CP_DECL_THREAD_LOCAL_P (decl)) + if (CP_DECL_THREAD_LOCAL_P (decl) && !DECL_REALLY_EXTERN (decl)) error_at (DECL_SOURCE_LOCATION (decl), "%qD declared % in %qs function", decl, DECL_IMMEDIATE_FUNCTION_P (current_function_decl) diff --git a/gcc/testsuite/g++.dg/cpp2a/constexpr-nonlit7.C b/gcc/testsuite/g++.dg/cpp2a/constexpr-nonlit7.C new file mode 100644 index 00000000000..06125756f25 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp2a/constexpr-nonlit7.C @@ -0,0 +1,6 @@ +// PR c++/104994 +// CWG2552 +// { dg-do compile { target c++14 } } + +constexpr bool foo () { extern thread_local int t; return true; } +static constexpr bool a = foo ();