From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id 9B9FC3858D1E; Tue, 8 Feb 2022 14:25:19 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 9B9FC3858D1E 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 r12-7105] libstdc++: Add comment to acinclude.m4 X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/heads/master X-Git-Oldrev: 676e987b850a7352ece750a8f3a1ac5dae6b3627 X-Git-Newrev: 8dbb60b8dfc642a81f1c41fde11767150e8f91a5 Message-Id: <20220208142519.9B9FC3858D1E@sourceware.org> Date: Tue, 8 Feb 2022 14:25:19 +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: Tue, 08 Feb 2022 14:25:19 -0000 https://gcc.gnu.org/g:8dbb60b8dfc642a81f1c41fde11767150e8f91a5 commit r12-7105-g8dbb60b8dfc642a81f1c41fde11767150e8f91a5 Author: Jonathan Wakely Date: Tue Feb 8 13:41:33 2022 +0000 libstdc++: Add comment to acinclude.m4 libstdc++-v3/ChangeLog: * acinclude.m4 (GLIBCXX_ENABLE_LOCK_POLICY): Add comment about checking for CAS on correct word size. Diff: --- libstdc++-v3/acinclude.m4 | 2 ++ 1 file changed, 2 insertions(+) diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4 index 7cc52f4db96..f53461c85a5 100644 --- a/libstdc++-v3/acinclude.m4 +++ b/libstdc++-v3/acinclude.m4 @@ -3609,6 +3609,8 @@ AC_DEFUN([GLIBCXX_ENABLE_LOCK_POLICY], [ ac_save_CXXFLAGS="$CXXFLAGS" dnl Why do we care about 2-byte CAS on targets with 4-byte _Atomic_word?! + dnl Why don't we check 8-byte CAS for sparc64, where _Atomic_word is long?! + dnl New targets should only check for CAS for the _Atomic_word type. AC_TRY_COMPILE([ #if ! defined __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 # error "No 2-byte compare-and-swap"