Re: Static const member initialization
On Jan 23, 11:38 am, Christian Kandeler <christian.kande...@hob.de>
wrote:
consider the following small program:
--------------------
#include <iostream>
#include <string>
class C1 {
std::string name;
public:
C1(const std::string& name_arg) : name(name_arg) { }
const std::string& get_name() const { return name; }
};
class C2 : public C1 {
static const std::string NAME;
public:
C2() : C1(NAME) { }
};
const std::string C2::NAME = "test";
int main()
{
C2 obj;
std::cout << obj.get_name() << std::endl;
return 0;
}
--------------------
I have tried it with two different compilers. Both compiled
it, but only one of the executables works. The other one
crashes with a segmentation fault; debugging shows that C2's
NAME member is uninitialized when C2() is called. Is this a
linker error? I would assume that a static member of a class
must be initialized before its first object is created. Who's
wrong here?
There's no guarantee that a static member of a class must be
initialized before its first object is created, but there is a
rule that objects with static lifetime (and class or namespace
scope) must be initialized before main is called. (The rule is
actually a bit more complicated, but in practice, it comes down
to "before main"; the exceptions don't apply here.)
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