From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 29969 invoked by alias); 17 Jul 2004 14:43:35 -0000 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org Received: (qmail 29952 invoked by uid 48); 17 Jul 2004 14:43:34 -0000 Date: Sat, 17 Jul 2004 14:43:00 -0000 Message-ID: <20040717144334.29951.qmail@sourceware.org> From: "ian at wasabisystems dot com" To: gcc-bugs@gcc.gnu.org In-Reply-To: <20040413135721.14940.ian@wasabisystems.com> References: <20040413135721.14940.ian@wasabisystems.com> Reply-To: gcc-bugzilla@gcc.gnu.org Subject: [Bug pch/14940] PCH largefile test fails on various platforms X-Bugzilla-Reason: CC X-SW-Source: 2004-07/txt/msg02137.txt.bz2 List-Id: ------- Additional Comments From ian at wasabisystems dot com 2004-07-17 14:43 ------- I should add that always using MAP_FIXED will cause the new mmap to clobber any existing memory maps, which will lead to silent failure if the GC code (or the library malloc code) happens to have mapped any portion of that memory space. So using MAP_FIXED does not work in general. For an example of how it can be used on some systems, see gcc/config/host-solaris.c, which uses mincore() to explicitly check whether anything else is mapped in that address space. But note that that code does not work on, e.g., GNU/Linux, because mincore() does not work as expected--it does not detect anonymous maps. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14940