goto statement
Transfers control unconditionally.
Used when it is otherwise impossible to transfer control to the desired location using other statements.
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[edit] Syntax
attr (optional) goto label ;
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[edit] Explanation
The goto statement transfers control to the location specified by label. The goto statement must be in the same function as the label it is referring, it may appear before or after the label.
If transfer of control exits the scope of any automatic variables (e.g. by jumping backwards to a point before the declarations of such variables or by jumping forward out of a compound statement where the variables are scoped), the destructors are called for all variables whose scope was exited, in the order opposite to the order of their construction.
The goto statement cannot transfer control into a control-flow-limited statement, but can transfer control out of a control-flow-limited statement (the rules above regarding automatic variables in scope are followed).
If transfer of control enters the scope of any automatic variables (e.g. by jumping forward over a declaration statement), the program is ill-formed (cannot be compiled), unless all variables whose scope is entered have the following types:
- scalar types declared without initializers
- class types with trivial default constructors and trivial destructors declared without initializers
- cv-qualified versions of one of the above
- arrays of one of the above
(Note: the same rules apply to all forms of transfer of control)
[edit] Notes
In the C programming language, the goto statement has fewer restrictions and can enter the scope of any variable other than variable-length array or variably-modified pointer.