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Article View: comp.std.c++
Article #3388

pointer conversions from the null pointer constant

#3388
From: Balasubramanian
Date: Tue, 20 Feb 1996 18:51
32 lines
1625 bytes
Given the following:

class A {};
class B : public A {};
class C : public B {};

void foo(A*) { ... }

void foo(C*) { ... }

int main() {foo(0); return 0;}

How is the call to foo() in main() to be resolved? It seemed obvious
to me that the call should be ambiguous but some compilers resolve
it as a call to foo(C*) (while others reject it as ambiguous.)

Is the conversion of the null pointer constant to C* 
better than its conversion to A*? I couldn't find anything
in the ARM or the draft standard (May 1995) to support this 
interpretation.

Thanks.


	- balu
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From: balu@netcom.com (Balasubramanian)
Newsgroups: comp.std.c++
Subject: pointer conversions from the null pointer constant
Date: 20 Feb 1996 10:51:57 PST
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