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* [Bug c++/23807] New: Mixed-type arithmetic error
@ 2005-09-10 14:12 igodard at pacbell dot net
  2005-09-10 14:33 ` [Bug c++/23807] " igodard at pacbell dot net
  2005-09-10 15:42 ` pinskia at gcc dot gnu dot org
  0 siblings, 2 replies; 3+ messages in thread
From: igodard at pacbell dot net @ 2005-09-10 14:12 UTC (permalink / raw)
  To: gcc-bugs

#include    <iostream>

int main () {
    unsigned short us = ~0;
    unsigned int ui = 1;
    unsigned int res = ui + us;
    std::cerr << "res: " << res << ", ui: " << ui << ", us: 0x"
        << std::hex << us << "\n";
    res = 1;
    res = res + us;
    std::cerr << "res: " << res << ", ui: " << ui << ", us: 0x"
        << std::hex << us << "\n";
    return 0;
    }


gets you:

~/ootbc/members/src$ g++ foo.cc
~/ootbc/members/src$ a.out
res: 65536, ui: 1, us: 0xffff
res: 10000, ui: 1, us: 0xffff


Compiler:
~/ootbc/members/src$ gcc -v
Reading specs from /mnt/export/local/bin/../lib/gcc/i686-pc-linux-gnu/3.4.0/specs
Configured with: ../gcc/configure --prefix=/site
Thread model: posix
gcc version 3.4.0

Appears to be an optimization error, and non-update (first) version gives
correct result.

-- 
           Summary: Mixed-type arithmetic error
           Product: gcc
           Version: 3.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: igodard at pacbell dot net
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23807


^ permalink raw reply	[flat|nested] 3+ messages in thread
* [Bug c++/23807] Mixed-type arithmetic error
  2005-09-10 14:12 [Bug c++/23807] New: Mixed-type arithmetic error igodard at pacbell dot net
@ 2005-09-10 14:33 ` igodard at pacbell dot net
  2005-09-10 15:42 ` pinskia at gcc dot gnu dot org
  1 sibling, 0 replies; 3+ messages in thread
From: igodard at pacbell dot net @ 2005-09-10 14:33 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From igodard at pacbell dot net  2005-09-10 14:33 -------
Simpler test case:
#include    <iostream>

int main () {
    unsigned short us = 0;
    unsigned int res = ~us;
    std::cerr << "res: 0x" << std::hex << res << ", us: 0x"  << us << "\n";
    return 0;
    }


gets you:

~/ootbc/members/src$ g++ foo.cc
~/ootbc/members/src$ a.out
res: 0xffffffff, us: 0x0



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23807


^ permalink raw reply	[flat|nested] 3+ messages in thread
* [Bug c++/23807] Mixed-type arithmetic error
  2005-09-10 14:12 [Bug c++/23807] New: Mixed-type arithmetic error igodard at pacbell dot net
  2005-09-10 14:33 ` [Bug c++/23807] " igodard at pacbell dot net
@ 2005-09-10 15:42 ` pinskia at gcc dot gnu dot org
  1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-09-10 15:42 UTC (permalink / raw)
  To: gcc-bugs


------- Additional Comments From pinskia at gcc dot gnu dot org  2005-09-10 15:42 -------
    unsigned int res = ~us;

Is equivant to:
    unsigned int res = ~(int)us;


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23807


^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2005-09-10 15:42 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2005-09-10 14:12 [Bug c++/23807] New: Mixed-type arithmetic error igodard at pacbell dot net
2005-09-10 14:33 ` [Bug c++/23807] " igodard at pacbell dot net
2005-09-10 15:42 ` pinskia at gcc dot gnu dot org

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