From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21051 invoked by alias); 19 Jun 2009 16:47:32 -0000 Received: (qmail 21021 invoked by uid 48); 19 Jun 2009 16:47:19 -0000 Date: Fri, 19 Jun 2009 16:47:00 -0000 Subject: [Bug libgomp/40494] New: omp for loop with guided schedule fails to terminate in certain cases X-Bugzilla-Reason: CC Message-ID: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "per at bitempire dot com" Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2009-06/txt/msg01368.txt.bz2 The following loop, which seems valid according to the OpenMP specification v2.5 and 3.0 fails to terminate: int x; #pragma omp parallel for schedule(guided) for(x = 3; x < 478; x += 2) { ... } I've tested with two and eight threads and different chunksizes, with the same non-termination result. Changing the upper bound to 477, however, makes the loop terminate, which leads me to belive this is an issue in the GNU OpenMP runtime library. I have confirmed that the problems exists in 4.2, 4.3 and 4.5 (trunk, 19-06-09). To me, bug 35625 seems somewhat similar but was supposedly fixed in 4.3. /Per -- Summary: omp for loop with guided schedule fails to terminate in certain cases Product: gcc Version: 4.2.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libgomp AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: per at bitempire dot com GCC build triplet: i686-pc-linux GCC host triplet: i686-pc-linux GCC target triplet: i686-pc-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40494