Re: function point of class function

From:
James Kanze <james.kanze@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Thu, 6 Mar 2008 00:46:02 -0800 (PST)
Message-ID:
<0e3c36da-32f2-4415-b1cc-9b9fd35ef707@8g2000hse.googlegroups.com>
On Mar 5, 3:16 pm, Ralf Goertz
<r_goe...@expires-2006-11-30.arcornews.de> wrote:

    [...]

Just don't forget to declare the wrapper `extern "C"'. For
the day when you compile with a compiler which isn't broken.
(Both VC++ and g++ are broken in this regard. Sun CC issues
an error message, however.)


Oh thanks, as you say, g++ didn't bark at me. But I thought
that a function that is explicitely declared as a C function
can't call a C++-function.


You're still compiling in C++. A function declared `extern "C"'
is a C++ function, and can be (and in fact must be, if its
definition is in a C++ source file) written in C++, using all of
the facilities of C++. The only difference is the way the
compiler generates its interface: if the function is `extern
"C"', the compiler generates the interface (function name,
calling conventions, etc.) as if it were a C function. (On most
platforms today, C and C++ use the same calling conventions, but
there's no real reason that this should be the case, and I've
used a compiler on Intel where they didn't.)

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