From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-297323-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 24776 invoked by alias); 22 Oct 2009 09:22:41 -0000
Received: (qmail 24673 invoked by uid 48); 22 Oct 2009 09:22:27 -0000
Date: Thu, 22 Oct 2009 09:22:00 -0000
Subject: [Bug c/41794]  New: About Long long bit field
X-Bugzilla-Reason: CC
Message-ID: <bug-41794-17793@http.gcc.gnu.org/bugzilla/>
Reply-To: gcc-bugzilla@gcc.gnu.org
To: gcc-bugs@gcc.gnu.org
From: "shenrfen at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
X-SW-Source: 2009-10/txt/msg01885.txt.bz2

Test case:

struct s
{
        unsigned long long a:2;
        unsigned long long b:40;
        unsigned long long c:22;
};

int main()
{
        struct s t = {1, 2, 3};
        printf("0x%llx\n",(t.b-8));
}

The output of gcc42 is 0xfffffffffa (which is yield to be 40bits)

Why not          0xfffffffffffffffa (It should be 64bits)


-- 
           Summary: About Long long bit field
           Product: gcc
           Version: 4.2.4
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: shenrfen at gmail dot com
 GCC build triplet: x86
  GCC host triplet: x86
GCC target triplet: x86


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41794