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You should note that a nonlocal goto, implemented by the Standard C library functions setjmp( ) and longjmp( ), doesn't cause destructors to be called. (This is the specification, even if your compiler doesn't implement it that way.
No, most destructors are not run on exit() . Essentially, when exit is called static objects are destroyed, atexit handlers are executed, open C streams are flushed and closed, and files created by tmpfile are removed.
A destructor is a member function that is invoked automatically when the object goes out of scope or is explicitly destroyed by a call to delete .
An explicit call to destructor is only necessary when an object is placed at a particular location in memory by using placement new. Destructor should not be called explicitly when the object is dynamically allocated because the delete operator automatically calls destructor.
The C++ Standard says:
On exit from a scope (however accomplished), destructors (12.4) are called for all constructed objects with automatic storage duration (3.7.2) (named objects or temporaries) that are declared in that scope, in the reverse order of their declaration.
So the answer is "yes".
Yes, they will be called.
Update: (it's okay to do this, gotos is not worse than throwing dummy exceptions or using bools/ifs to get out of things. A simple goto inside a function don't make it spaghetti code.)
1) Yes. 2) Don't do this.
Elaboration: conceptually, this is no different from leaving a loop via a break. goto, however, is strongly, strongly discouraged. It is almost never necessary to use goto, and any use should be scrutinized to find out what's going on.
Yes, as everyone else says. C++ specifies/mandates this.
But just to add to that, for completeness: if your goto uses the computed-goto extension found in some compilers -- gcc, clang, possibly others but not including MSVC last I knew -- whether or not the object's destructor will be called is pretty hazy. When a goto goes to a single location, it's very clear what destructors must be called before the control-flow transfer. But with a computed goto, different destructors might need to dynamically be called, to give the "expected" semantics. I'm not sure what compilers that implement this extension do, in those cases. My memory from encountering this is that clang warns when a computed-goto might leave a scope with an object with a non-trival destructor, claiming the destructor won't be called. In some cases that might be fine, in others not. I don't know offhand what other compilers do. Just be aware of the issue if you want to use computed gotos in concert with objects with non-trivial destructors.
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