Is this a Bug of VS 2005?

[Lighter]

Is this a Bug of VS 2005?

We know size_t is not a built-in data type in C++, rather, it is just a
typedef declaration.

However, I found the following code could be normally compiled with VS
2005:

// Note that I don't include any header file in this source file

size_t Test(size_t a)
{
return a;
}

int main()
{
size_t n = Test(8);

return n;
}

Why? Is this really a bug of VS 2005?

[Jack Klein]

On 3 Aug 2006 21:38:52 -0700, "Lighter" <cq****@gmail.c omwrote in
comp.lang.c++:

Is this a Bug of VS 2005?

No.

We know size_t is not a built-in data type in C++, rather, it is just a
typedef declaration.

However, I found the following code could be normally compiled with VS
2005:

// Note that I don't include any header file in this source file

size_t Test(size_t a)
{
return a;
}

int main()
{
size_t n = Test(8);

return n;
}

Why? Is this really a bug of VS 2005?

It can be considered an extension, and extensions are perfectly valid
as long as they do not affect the behavior of a strictly conforming
program. And this can't, because the program has undefined behavior
by using an undefined type.

Furthermore, an attempt to cause a conflict by adding something like:

typedef double size_t;

....in your source file causes even more undefined behavior because all
typedef's inherited from the C library, which includes size_t, are
reserved for the compiler in both the global and std namespaces.

--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
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alt.comp.lang.l earn.c-c++
http://www.contrib.andrew.cmu.edu/~a...FAQ-acllc.html

[Lighter]

to Jack Klein:

Thank you for your answer. However, I don't think this is an extension
for C++ made by VS 2005. The reason for this is that VS 2005 can still
correctly compile the code above-mentioned even I set the compiler
option /Za.

[Darwin Lalo]

Lighter 写�：

Is this a Bug of VS 2005?

We know size_t is not a built-in data type in C++, rather, it is just a
typedef declaration.

However, I found the following code could be normally compiled with VS
2005:

// Note that I don't include any header file in this source file

size_t Test(size_t a)
{
return a;
}

int main()
{
size_t n = Test(8);

return n;
}

Why? Is this really a bug of VS 2005?

Some "Header Files" is Default Includes.

[Lighter]

Darwin Lalo wrote:

Some "Header Files" is Default Includes.

Are you sure? Where can I find the reference?

[Ian Collins]

Darwin Lalo wrote:

>
Some "Header Files" is Default Includes.

Name one.

--
Ian Collins.

[Alf P. Steinbach]

* Jack Klein:

On 3 Aug 2006 21:38:52 -0700, "Lighter" <cq****@gmail.c omwrote in
comp.lang.c++:

>Is this a Bug of VS 2005?

No.

>We know size_t is not a built-in data type in C++, rather, it is just a
typedef declaration.

However, I found the following code could be normally compiled with VS
2005:

// Note that I don't include any header file in this source file

size_t Test(size_t a)
{
return a;
}

int main()
{
size_t n = Test(8);

return n;
}

Why? Is this really a bug of VS 2005?

It can be considered an extension,

Yes.

and extensions are perfectly valid
as long as they do not affect the behavior of a strictly conforming
program.

Yes, but a diagnostic must be issued (in standards-compliant mode). The
compiler can then go on to compile the rest with no further diagnostics.

I think it's a bug, possibly one intentionally introduced to make some
code that relies on this behavior, compile cleanly.
--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

[Ron Natalie]

Jack Klein wrote:

>
It can be considered an extension, and extensions are perfectly valid
as long as they do not affect the behavior of a strictly conforming
program. And this can't, because the program has undefined behavior
by using an undefined type.

Except the compiler should say something. The program is ill-formed.

[Darwin Lalo]

Many years ago, I read it.
I think it it's trivial.
"NULL" is the same.

Darwin Lalo wrote:

Some "Header Files" is Default Includes.

Are you sure? Where can I find the reference?

[Darwin Lalo]

Ian Collins wrote:

Darwin Lalo wrote:

Some "Header Files" is Default Includes.

Name one.

<stdlib.h>