[Bug c++/35669] NULL (__null) not considered different from 0 with C++

[peter at cordes dot ca]

------- Comment #8 from peter at cordes dot ca  2009-02-12 17:56 -------
Would it cause any problems for g++ to behave more like a C compiler when it
comes to NULL?  e.g. I found this bug report after finding that kscope 1.9.1
didn't compile, because it expected NULL to match the void* version of an
overloaded function.

locationlistmodel.cpp:204: error: call of overloaded ‘createIndex(int&, int&,
NULL)Â’ is ambiguous

.../qabstractitemmodel.h:288: note: candidates are: QModelIndex
QAbstractItemModel::createIndex(int, int, void*) const
.../qabstractitemmodel.h:290: note:                 QModelIndex
QAbstractItemModel::createIndex(int, int, int) const
.../qabstractitemmodel.h:299: note:                 QModelIndex
QAbstractItemModel::createIndex(int, int, quint32) const

This was in released alpha code
(http://qt-apps.org/content/show.php?content=96992) so presumably it built ok
on some compiler.  (Although maybe it used to just pick one of the int
overloads, if that's what Lubos was talking about having to debug.)

 As a mostly C programmer, this just seems like something stupid in the
standard, and the sort of behaviour you should only get with -std=c++0x, but
not -std=gnu++0x.  As everyone else is saying, who in their right mind actually
wants this behaviour?  And more importantly, would changing it ever make g++
actually mis-compile anything?  (not counting compiling stuff like kscope, or
test.c below, where the result "should" be an error message, not a binary)

 Anyway, NULL should be a void*, damn it.  Yes, I'm a C programmer.


-- 

peter at cordes dot ca changed:

           What    |Removed                     |Added
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                 CC|                            |peter at cordes dot ca


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35669