From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11110 invoked by alias); 22 Mar 2014 00:21:28 -0000 Mailing-List: contact jit-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Post: List-Help: List-Subscribe: Sender: jit-owner@gcc.gnu.org Received: (qmail 11087 invoked by uid 89); 22 Mar 2014 00:21:26 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Checked: by ClamAV 0.98.1 on sourceware.org X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.2 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-Spam-Status: No, score=-2.2 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on sourceware.org X-Spam-Level: X-Spam-User: qpsmtpd, 2 recipients X-HELO: mx1.redhat.com Message-ID: <1395440318.10979.10.camel@surprise> Subject: Re: [RFA jit] initialize input_location From: David Malcolm To: Tom Tromey Cc: jit@gcc.gnu.org, gcc-patches@gcc.gnu.org Date: Wed, 01 Jan 2014 00:00:00 -0000 In-Reply-To: <1395327187-14524-1-git-send-email-tromey@redhat.com> References: <1395327187-14524-1-git-send-email-tromey@redhat.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-SW-Source: 2014-q1/txt/msg00095.txt.bz2 On Thu, 2014-03-20 at 08:53 -0600, Tom Tromey wrote: > This patch initializes input_location at the same spot where the line > table is initialized. Without this, it's possible to crash when > emitting a diagnostic in a reinvocation of the compiler, because > input_location refers to a location that is no longer valid. > --- > gcc/ChangeLog.jit | 4 ++++ > gcc/toplev.c | 1 + > 2 files changed, 5 insertions(+) > > diff --git a/gcc/ChangeLog.jit b/gcc/ChangeLog.jit > index ee1df88..a9b0817 100644 > --- a/gcc/ChangeLog.jit > +++ b/gcc/ChangeLog.jit > @@ -1,5 +1,9 @@ > 2014-03-19 Tom Tromey > > + * toplev.c (general_init): Initialize input_location. > + > +2014-03-19 Tom Tromey > + > * timevar.h (auto_timevar): New class. > > 2014-03-19 Tom Tromey > diff --git a/gcc/toplev.c b/gcc/toplev.c > index b257ab2..1febc2e 100644 > --- a/gcc/toplev.c > +++ b/gcc/toplev.c > @@ -1161,6 +1161,7 @@ general_init (const char *argv0) > table. */ > init_ggc (); > init_stringpool (); > + input_location = 0; > line_table = ggc_alloc_line_maps (); > linemap_init (line_table); > line_table->reallocator = realloc_for_line_map; Given this declaration in input.c: location_t input_location; then assigning 0 is a faithful way of resetting it to its initial state. That said, "0" feels like a magic number. Would it better to assign UNKNOWN_LOCATION to it? which is 0, c.f. input.h: #define UNKNOWN_LOCATION ((source_location) 0) If so, perhaps the declaration in input.c should gain an initializer to the same value? (shouldn't affect the code, since it's 0 either way, but perhaps it's more readable?) Dave