From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 93076 invoked by alias); 29 Aug 2019 16:36:40 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 93068 invoked by uid 89); 29 Aug 2019 16:36:40 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-8.5 required=5.0 tests=AWL,BAYES_00,GIT_PATCH_2,GIT_PATCH_3,SPF_HELO_PASS autolearn=ham version=3.3.1 spammy= X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 29 Aug 2019 16:36:39 +0000 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3DA8B8B5FF0; Thu, 29 Aug 2019 16:36:38 +0000 (UTC) Received: from localhost (unused-10-15-17-196.yyz.redhat.com [10.15.17.196]) by smtp.corp.redhat.com (Postfix) with ESMTP id BF7EB60C05; Thu, 29 Aug 2019 16:36:37 +0000 (UTC) From: Sergio Durigan Junior To: Pedro Alves Cc: GDB Patches , Bernhard Wodok , Paul Carroll Subject: Re: [PATCH] Fix PR win32/24284: tcp_auto_retry doesn't work in MinGW References: <20190827155013.31610-1-sergiodj@redhat.com> <64a05dd3-ad63-eb64-49b4-cbc5faf51824@redhat.com> Date: Thu, 29 Aug 2019 16:36:00 -0000 In-Reply-To: <64a05dd3-ad63-eb64-49b4-cbc5faf51824@redhat.com> (Pedro Alves's message of "Thu, 29 Aug 2019 13:15:41 +0100") Message-ID: <87zhjs9be2.fsf@redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-IsSubscribed: yes X-SW-Source: 2019-08/txt/msg00647.txt.bz2 On Thursday, August 29 2019, Pedro Alves wrote: > On 8/27/19 4:50 PM, Sergio Durigan Junior wrote: >> This was reported by Bernhard Wodok, along with a patch to fix the >> issue. I adjusted the patch a bit, and I'm submitting the patch on >> his behalf. >> >> According to Bernhard, the issue can be reproduced by doing: >> >> 1. start gdb >> 2. enter 'target remote :2345' >> 3. observe that it throws a "connection refused" error immediately >> instead of waiting and throwing a timeout error >> >> I.e., I believe it can be reproduced by our current tests, which is >> why I'm not proposing any extra tests here (well, I don't use nor have >> any Windows system to test this, so...). >> >> The problem happens because we call 'gdb_select' passing 0 as its >> first argument, Thanks for the review, Pedro. > I assume this is from wait_for_connect? Please mention that above. Yes. I'll do that. > Must be, because I just now noticed that gdb_usleep is now dead code. > > The comment in wait_for_connect is quite curious, kind of implies that > this worked on Windows at some point: > > /* Use gdb_select here, since we have no file descriptors, and on > Windows, plain select doesn't work in that case. */ > n = gdb_select (0, NULL, NULL, NULL, &t); Indeed. This comment was added by: commit 84603566b73e9ad18d094da3b7510ab480db8170 Author: Sandra Loosemore Date: Tue Jan 6 17:07:08 2009 +0000 It's not entirely clear that calling gdb_select on Windows will actually call WaitForMultipleObjects. There is a 'select'c call in the Windows API: https://docs.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-select So maybe it was assumed that the code would call this function instead... >> --- a/gdb/mingw-hdep.c >> +++ b/gdb/mingw-hdep.c >> @@ -64,6 +64,17 @@ gdb_select (int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, >> int num_ready; >> size_t indx; >> >> + if (n == 0) >> + { >> + /* The MS API says that the first argument to >> + WaitForMultipleObjects cannot be zero. That's we just use >> + a regular Sleep here. */ > > The sentence: > > "That's we just use a regular Sleep here." > > is non-grammatical. Missing a "why" in "That's why" ? Yes, fixed. > OK with that fixed. Thanks, pushed: 16d01f9cd49f553a958a69ad3c9f781ebd402da8 -- Sergio GPG key ID: 237A 54B1 0287 28BF 00EF 31F4 D0EB 7628 65FC 5E36 Please send encrypted e-mail if possible http://sergiodj.net/