------- Comment #10 from bangerth at gmail dot com 2009-04-29 12:51 -------
There is really nothing much that can be done within the current C++
standard. In C, NULL is defined as
(void*)0
which can be converted to any other pointer and so is clearly marked
as a pointer. The compiler can then warn when passing it to an integer
argument of a function.
In C++, we have [18.1/4] "The macro NULL is an implementation-defined C++ null
pointer constant in this International Standard (_conv.ptr_).180)" and
footnote 180 specifically says:
180) Possible definitions include 0 and 0L, but not (void*)0.
This is because void* is not implicitly convertible to any other pointer
type and so NULL could not be assigned to other pointers. As a consequence,
since NULL can not in an obvious way be a pointer, there is no obvious
warning that can be generated.
The situation will be different with the upcoming C++1x standard where there
is null_ptr.
W.
--
bangerth at gmail dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |bangerth at gmail dot com
Status|UNCONFIRMED |RESOLVED
Resolution| |WONTFIX
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35669
