public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug c++/20123] New: mangled name of typeid doesn't encode cv-qualifer.
@ 2005-02-21 23:12 yanliu at ca dot ibm dot com
2005-02-21 23:15 ` [Bug c++/20123] " pinskia at gcc dot gnu dot org
` (2 more replies)
0 siblings, 3 replies; 5+ messages in thread
From: yanliu at ca dot ibm dot com @ 2005-02-21 23:12 UTC (permalink / raw)
To: gcc-bugs
Here is a testcase:
#include <typeinfo>
int const volatile v5[10] = {0};
int
main (int argc, char **argv) {
const std::type_info& t = typeid (::v5);
}
According to Itanium C++ ABI, the mangled name of typeid(::v5) should follow
the following grammer rules:
<mangled-name> ::= _Z <encoding>
<encoding> ::= <special-name>
<special-name> ::= TI <type> # typeinfo structure
<type> ::= <array-type>
<array-type> ::= A <positive dimension number> _ <element type>
To my understanding, the element type follows the <type> rule and is used to
encode the type of variable v5[10]:
<type> ::= <CV-qualifiers> <type>
<CV-qualifiers> ::= [r] [V] [K] # restrict (C99), volatile,
const
So the mangled name should be: __ZTIA10_VKi. But using gcc 4.0 compiler, I am
getting "__ZTIA10_i" mangled name instead.
Please verify the problem, thanks.
--
Summary: mangled name of typeid doesn't encode cv-qualifer.
Product: gcc
Version: 4.0.0
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: yanliu at ca dot ibm dot com
CC: gcc-bugs at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20123
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/20123] mangled name of typeid doesn't encode cv-qualifer.
2005-02-21 23:12 [Bug c++/20123] New: mangled name of typeid doesn't encode cv-qualifer yanliu at ca dot ibm dot com
@ 2005-02-21 23:15 ` pinskia at gcc dot gnu dot org
2005-02-21 23:35 ` yanliu at ca dot ibm dot com
2005-02-24 23:45 ` jody-atd-030903 at atdesk dot com
2 siblings, 0 replies; 5+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-02-21 23:15 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2005-02-21 19:17 -------
hmm, ICC 8.0 on ia32-linux produces the same mangled name for the variable too.
--
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |ABI
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20123
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/20123] mangled name of typeid doesn't encode cv-qualifer.
2005-02-21 23:12 [Bug c++/20123] New: mangled name of typeid doesn't encode cv-qualifer yanliu at ca dot ibm dot com
2005-02-21 23:15 ` [Bug c++/20123] " pinskia at gcc dot gnu dot org
@ 2005-02-21 23:35 ` yanliu at ca dot ibm dot com
2005-02-24 23:45 ` jody-atd-030903 at atdesk dot com
2 siblings, 0 replies; 5+ messages in thread
From: yanliu at ca dot ibm dot com @ 2005-02-21 23:35 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From yanliu at ca dot ibm dot com 2005-02-21 19:37 -------
For function parameters, the cv-qualifers should not be mangled. I suspect GCC
treates this typeid as a function, thus ignoring the encoding of cv-qualifers.
At least, the C++ ABI is not clear in this aspect.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20123
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/20123] mangled name of typeid doesn't encode cv-qualifer.
2005-02-21 23:12 [Bug c++/20123] New: mangled name of typeid doesn't encode cv-qualifer yanliu at ca dot ibm dot com
2005-02-21 23:15 ` [Bug c++/20123] " pinskia at gcc dot gnu dot org
2005-02-21 23:35 ` yanliu at ca dot ibm dot com
@ 2005-02-24 23:45 ` jody-atd-030903 at atdesk dot com
2 siblings, 0 replies; 5+ messages in thread
From: jody-atd-030903 at atdesk dot com @ 2005-02-24 23:45 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From jody-atd-030903 at atdesk dot com 2005-02-24 19:33 -------
I am not on the gcc team, so feel free to take this with some reservation.
According to 5.2.8.5, the top-level cv-qualifier are stripped when calling typeid().
According to 3.9.3.[2,5], cv-qualifiers applied to array types apply to the
array elements, not to the array.
Thus, I think the name you see is correct. In your example, you should be able
to see typeid() doing the right thing (and see that the top-level cv-qualifers
are being stripped) with...
int x[10];
assert(typeid(::v5) == typeid(int[10]));
assert(typeid(::v5) == typeid(x));
assert(strcmp(typeid(::v5).name(), typeid(x).name()) == 0);
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20123
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/20123] mangled name of typeid doesn't encode cv-qualifer.
[not found] <bug-20123-5317@http.gcc.gnu.org/bugzilla/>
@ 2009-03-05 18:35 ` jason at gcc dot gnu dot org
0 siblings, 0 replies; 5+ messages in thread
From: jason at gcc dot gnu dot org @ 2009-03-05 18:35 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from jason at gcc dot gnu dot org 2009-03-05 18:35 -------
Jody's comment is correct; typeid represents the cv-unqualified type of the
expression, which for an array lvalue means removing the cv qualifiers from the
array.
--
jason at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution| |INVALID
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20123
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2009-03-05 18:35 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2005-02-21 23:12 [Bug c++/20123] New: mangled name of typeid doesn't encode cv-qualifer yanliu at ca dot ibm dot com
2005-02-21 23:15 ` [Bug c++/20123] " pinskia at gcc dot gnu dot org
2005-02-21 23:35 ` yanliu at ca dot ibm dot com
2005-02-24 23:45 ` jody-atd-030903 at atdesk dot com
[not found] <bug-20123-5317@http.gcc.gnu.org/bugzilla/>
2009-03-05 18:35 ` jason at gcc dot gnu dot org
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).