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From: pme@gcc.gnu.org To: gcc-gnats@gcc.gnu.org Subject: libstdc++/6282: bitset<0> results in nonsense behavior Date: Fri, 12 Apr 2002 13:16:00 -0000 [thread overview] Message-ID: <20020412200824.18100.qmail@sources.redhat.com> (raw) >Number: 6282 >Category: libstdc++ >Synopsis: bitset<0> results in nonsense behavior >Confidential: no >Severity: critical >Priority: low >Responsible: unassigned >State: open >Class: sw-bug >Submitter-Id: net >Arrival-Date: Fri Apr 12 13:16:00 PDT 2002 >Closed-Date: >Last-Modified: >Originator: Phil Edwards >Release: 3.x >Organization: >Environment: All. (Not platform-specific code.) >Description: Creating a std::bitset instance of zero size still stores a word's worth of data. Consider std::bitset<1> x(555555); int i = x.count(); Only the least significant bit from 555555 will be stored, and i will correctly be set to 1 (the count of "on" bits in x). But if x is defined as std::bitset<0> x(555555); then there are still sizeof(unsigned long) bits being stored and initialized, and x.count() returns 9 instead of the more correct 0. Other bitset member functions return likewise silly results. The base class for bitset is not taking into account the empty case. >How-To-Repeat: >Fix: >Release-Note: >Audit-Trail: >Unformatted:
next reply other threads:[~2002-04-12 20:16 UTC|newest] Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top 2002-04-12 13:16 pme [this message] 2002-04-12 13:28 pme 2002-05-24 11:22 pme
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