public inbox for gcc-prs@sourceware.org help / color / mirror / Atom feed
From: igor@txc.com To: gcc-gnats@gcc.gnu.org Subject: optimization/5470: bad optimization Date: Wed, 23 Jan 2002 14:46:00 -0000 [thread overview] Message-ID: <20020123224201.3202.qmail@sources.redhat.com> (raw) >Number: 5470 >Category: optimization >Synopsis: bad optimization >Confidential: no >Severity: serious >Priority: medium >Responsible: unassigned >State: open >Class: sw-bug >Submitter-Id: net >Arrival-Date: Wed Jan 23 14:46:08 PST 2002 >Closed-Date: >Last-Modified: >Originator: igor@txc.com >Release: gcc-3.0.2 >Organization: >Environment: hppa64-hp-hpux11.00 >Description: A test case program runs incorrectly when compiled with -O1 or higher: # define VERYBIGINT (9223372036854775807L) /* 2^63-1 */ unsigned long bound(unsigned long b) { unsigned long w; printf("b=%ld\n",b); for(w=0;w<=b;w++) { puts("loop gets executed"); return(w); } puts("loop doesn't get executed"); return(-1); } main() { printf("size of unsigned long type is %d bytes\n",sizeof(unsigned long)); exit(bound(VERYBIGINT)); } >How-To-Repeat: % gcc -o hpbug hpbug.c % ./hpbug size of long type is 8 bytes b=9223372036854775807 loop gets executed % gcc -O1 -o hpbug hpbug.c % ./hpbug size of long type is 8 bytes b=9223372036854775807 loop doesn't get executed >Fix: >Release-Note: >Audit-Trail: >Unformatted:
reply other threads:[~2002-01-23 22:46 UTC|newest] Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20020123224201.3202.qmail@sources.redhat.com \ --to=igor@txc.com \ --cc=gcc-gnats@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).