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Gcc Error Constructor Is Private

In other words, the order of the initialization list should mimic the order in which initializations will take place. However, the standard clearly states (12.2 par 1): "Even when the creation of the temporary object is avoided (12.8), all the semantic restrictions must be respected as if the temporary object Note: even though the object pointed to by ans in the previous FAQ is never deleted, the memory doesn't actually "leak" when the program exits since the operating system automatically reclaims TODO: WRITE THIS UP TODO: WRITE UP TRADEOFFS -- now that you know how to use the Nifty Counter Idiom, be sure you understand both when and (especially!) when not to

Or did I mention that you ought to use a std::vector unless there is a compelling reason to use an array? How did my int turn into a complex number? Because the return-by-value optimization causes the compiler to generate less code, it actually improves compile-times in addition to making your generated code smaller and faster. Just say no. http://stackoverflow.com/questions/7420296/private-constructor-error-c

Here is something that always works: the {body} of a constructor (or a function called from the constructor) can reliably access the data members declared in a base class and/or the As you recall, static local are only initialized once (the first time control flows over their declaration), so this will call X::x() only once: the first time X::someMethod() is called: void Next by Date: Re: What's up with "Constructor is private within this context"? What is the "Named Parameter Idiom"?

Appease Your Google Overlords: Draw the "G" Logo Physically locating the server Meaning of "oh freak" Why was the identity of the Half-Blood Prince important to the story? Shouldn't this expression successfully compile and result in 0? In a constructor's initialization list, it is easiest and safest to avoid using one member object from this object in the initialization expression of a subsequent initializer for this object. share|improve this answer answered Oct 13 '09 at 15:42 David Seiler 7,5731933 gcc can't optimize the constructors like that, since they have side effects (the couts).

Putting pin(s) back into chain True or False? Warning: it's compiler- and hardware-dependent: you'll need to make sure the storage is aligned with an alignment that is at least as strict as is required for objects of class Fred. Unfortunately it's very hard to detect -- the errors often occur before main() begins. dig this c++ copy-constructor assignment-operator share|improve this question edited Jan 20 '13 at 16:43 svick 124k23196308 asked Oct 13 '09 at 15:32 sdumi 634 1 FWIW: The code does compile if you

That's inefficient. Furthermore, if the various member functions are inline, the generated object code will probably be on par with C-style code that sets various members of a struct. Warning: it's ugly: the raw array can't be of type Fred, so you'll need a bunch of pointer-casts to do things like compute array index operations. private: Point(float x, float y); // Rectangular coordinates float x_, y_; }; inline Point::Point(float x, float y) : x_(x), y_(y) { } inline Point Point::rectangular(float x, float y) { return Point(x,

Does chilli get milder with cooking? have a peek at this web-site Browse other questions tagged c++ inheritance c++11 private default-constructor or ask your own question. If I'm right, the copy constructor is not being run because GCC can optimize away the redundant temporary; this is permitted by the C++ spec. Comment 4 Ville Voutilainen 2015-08-21 14:59:28 UTC Sorry for the noise, I managed to drop out that last line, bummer.

This may or may not be what you intended, but this is what happens. share|improve this answer answered Sep 14 '11 at 17:19 Mark B 76.6k465138 add a comment| up vote 1 down vote You are. So you are certainly doing one or both of these case somewhere in your code. That is often innocuous, since the operating system will typically clean up a process's memory when the process terminates.

Description Liviu 2004-05-03 02:32:18 UTC When declaring a friend function to a templetized class, function does not have access to private methods: test.h ================== template class foo; template

Some people do it anyway. Foo(x, 0); // Does NOT help initialize the this object!! // ... } You can sometimes combine two constructors via a default parameter: class Foo { public: Foo(char x, int y Do I need to dig out my copy of the C++ standard or is it something to file a bugreport?

Constructors are like "init functions".

For example, if there are 3 static objects, say a, b and c, that use ans during their destructors, the only way to avoid a static deinitialization disaster is if ans Comment 3 Gabriel Dos Reis 2001-08-12 02:09:20 UTC State-Changed-From-To: open->analyzed State-Changed-Why: The compiler is at fault on f.test (b). I ran this code: class B { public: B( int i ) { } private: B() { } }; class D : public B { public: D(int i) : B(i) { Before going through the caveats, here is a simple example that is allowed: // Fred.h class Fred { public: static const int maximum = 42; // ... }; And, as with

Why do train companies require two hours to deliver your ticket to the machine? Yes, though with some important caveats. Sorry for the confusion and thanks a lot for your time! You are guaranteed to find out whether it works or fails at compile-time, so if it compiles cleanly, it will work at runtime.

Terms of Use Privacy Policy All rights reserved. The standard states: The temporary should be initialized (8.5.3 par 5)"using the rules for a non-reference copy initialization (8.5)". Bug53734 - std::is_constructible fails to compile if copy constructor is private Summary: std::is_constructible fails to compile if copy constructor is private Status: RESOLVED DUPLICATE of bug 51213 Alias: None Product: gcc

Does the local exist as a separate object, or does it get optimized away? protected: unsigned len_; char* data_; }; MyString::MyString() : len_(0u) , data_(new char[1]) { data_[0] = '\0'; } MyString::~MyString() { delete[] data_; } MyString::MyString(const MyString& s) : len_ (s.len_) , data_(new char[s.len_ In particular, all(?) commercial-grade C++ compilers will optimize this case: Foo rbv() { // ... How do I prevent the "static initialization order fiasco" for my static data members?

share|improve this answer answered Oct 13 '09 at 15:48 CAdaker 6,58021928 Can you try to recompile in these versions using -Wall? Nope. Short answer: it's possible to use a static object rather than a static pointer, but doing so opens up another (equally subtle, equally nasty) problem. The bad news is that you have to know those language rules (e.g., base class sub-objects are initialized first (look up the order if you have multiple and/or virtual inheritance!), then

But it is right on f.test2(b): Argument passing by value is copy-initialization and the copy-constructor needs to be accessible even if it is elided. -- Gaby Comment 4 Mark Mitchell 2001-11-29 We could only guess at where. Not sure if it's important but I'm using: $ g++ --version g++ (GCC) 4.1.2 20080704 (Red Hat 4.1.2-44) Copyright (C) 2006 Free Software Foundation, Inc. Note: There is no performance difference if the type of x_ is some built-in/intrinsic type, such as int or char* or float.

When your code returns a local variable by value, your compiler might optimize away the local variable completely - zero space-cost and zero time-cost - the local variable never actually exists c++ inheritance c++11 private default-constructor share|improve this question edited Feb 22 '13 at 21:38 Jonathan Wakely 101k9165296 asked Feb 22 '13 at 17:09 Peregring-lk 2,4561440 add a comment| 1 Answer 1 I hear they're hiring down at McDonalds. You must be trying to instantiate an object of type GameDirector somewhere.

Constructors do a bunch of little magical things behind the scenes, but that bad technique steps on those partially constructed bits.

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