Btw., I should mention that I have no objection to immediately
committing the first part of this patch, i.e., everything but
the #ifdefs and the CREF() macro. That we can deal with later.
Martin
Martin Sebor wrote:
Farid Zaripov wrote:
-----Original Message-----
From: Martin Sebor [mailto:[EMAIL PROTECTED] Sent: Wednesday,
March 28, 2007 10:35 PM
To: [email protected]
Subject: Re: [PATCH] dynatype.cpp example and MSVC
This looks familiar. Didn't I already review this patch?
[...searching archives...]
I see you original patch in our archive (http://tinyurl.com/ywxq9w)
but I can't find my reply there. I was able to find it here though:
http://www.mail-archive.com/[email protected]/ms
g02760.html
but I haven't found any further follow-ups on the issues I raised,
either from you or anyone else.
I have not received the reply from you.
Yeah, the lists (or at least the archives) seem to have some
problems. I've opened another issue for these missing emails
with the infrastructure team:
https://issues.apache.org/jira/browse/INFRA-1209
@@ -105,27 +105,19 @@
// 14.7.3, p6 - explicit specializations must be defined before
first
use
template <>
-inline void dynatype::remove<dynatype::map<void> >()
+inline void dynatype::remove<void>()
The replacement doesn't look equivalent to the original. Is it correct
for compilers other than MSVC?
Why not?
Only because void isn't the same thing as dynatype::map<void>.
The dynatype::remove<dynatype::map<void> > used only in default
constructor,
because the dynatype::map<void> type is private type, so here that type
can be
replaced to the type void.
I think I understand what you did now. I also tested the patch
with both the latest EDG eccp as well as gcc so the change must
be good. Thanks for your patience :)
This change deals with MSVC error:
dynatype.cpp(109) : error C2248: 'dynatype::map<T>' : cannot access
private struct declared in class 'dynatype'
with
[
T=void
]
dynatype.cpp(31) : see declaration of 'dynatype'
The dynatype::operator= (const dynatype::map<void>&) removed because
it's never used.
Could it ever be used? Imagine dynatype being a general class
provided by a library. Does there exist a valid use case for
this operator? If not, I have no problem with removing it.
Otherwise, if it doesn't break anything, let's keep it.
The CREF macro used to resolve ambiguity between dynatype::operator T&
() and dynatype::operator T () const:
This was and still is my objection to this patch. As I said
in my initial comments on it:
The examples should be portable C++, i.e., free of #ifdef's
and other platform-specific workarounds. Unless there's a
way to get it to work with the compiler I'm not sure we
should pollute the code with hacks for broken compilers.
Can you think of a way to work around this bug that doesn't
involve MSVC-specific #ifdefs or macros?
dynatype.cpp(188) : error C2440: 'type cast' : cannot convert from
'dynatype' to 'int'
Ambiguous user-defined-conversion
Btw., do you have a test case for the MSVC bug that prevents the code
from compiling?
The first test:
Excellent! Can I ask you to do the usual two things:
1. Report this issue to Microsoft (http://tinyurl.com/yq66vu).
2. Copy the text of the issue to Jira.
If you don't have a Microsoft Connect account you should
create one (it's free). If you run into any trouble let me
know, I can either help you get it set up, try to get you
help from someone at Microsoft, or file the bug myself.
Martin
-----------------------------------
class test
{
struct private_t;
template <class T>
int foo () {
return 1;
}
};
template <>
int test::foo<test::private_t> ()
{
return 2;
}
int main ()
{
return 0;
}
-----------------------------------
test.cpp(13) : error C2248: 'test::private_t' : cannot access private
struct declared in class 'test'
test.cpp(3) : see declaration of 'test::private_t'
test.cpp(2) : see declaration of 'test'
The second test:
-----------------------------------
class test
{
public:
template <class T>
operator T& () {
static T x_;
return x_;
}
template <class T>
operator T () const {
return T (1);
}
};
int main ()
{
test t;
int x = int (t);
return 0;
}
-----------------------------------
test.cpp(19) : error C2440: 'type cast' : cannot convert from 'test' to
'int'
Ambiguous user-defined-conversion
Farid.
