Dev C++ Error Jump To Case Label
The default label can appear only once. The labeled statements are not syntactic requirements, but the switch statement is meaningless without them. The default statement need not come at the end; it can appear anywhere in the body of the switch statement. A case or default label can only appear inside a switch statement. The constant. Compilers may issue warnings on fallthrough (reaching the next case label without a break) unless the attribute fallthrough appears immediately before the case label to indicate that the fallthrough is intentional. If init-statement is used, the switch statement is equivalent to.
-->Microsoft Specific
Like an ordinary C or C++ label, a label in an __asm block has scope throughout the function in which it is defined (not only in the block). Both assembly instructions and goto statements can jump to labels inside or outside the __asm block.
Labels defined in __asm blocks are not case sensitive; both goto statements and assembly instructions can refer to those labels without regard to case. C and C++ labels are case sensitive only when used by goto statements. Assembly instructions can jump to a C or C++ label without regard to case.
The following code shows all the permutations:
Don't use C library function names as labels in __asm blocks. For instance, you might be tempted to use exit as a label, as follows:
Because exit is the name of a C library function, this code might cause a jump to the exit function instead of to the desired location.
As in MASM programs, the dollar symbol ($) serves as the current location counter. It is a label for the instruction currently being assembled. In __asm blocks, its main use is to make long conditional jumps:
END Microsoft Specific
See also
Inline Assembler
- C++ Basics
- C++ Object Oriented
- C++ Advanced
- C++ Useful Resources
- Selected Reading
A switch statement allows a variable to be tested for equality against a list of values. Each value is called a case, and the variable being switched on is checked for each case.
Syntax
The syntax for a switch statement in C++ is as follows −
The following rules apply to a switch statement −
The expression used in a switch statement must have an integral or enumerated type, or be of a class type in which the class has a single conversion function to an integral or enumerated type.
You can have any number of case statements within a switch. Each case is followed by the value to be compared to and a colon.
The constant-expression for a case must be the same data type as the variable in the switch, and it must be a constant or a literal.
When the variable being switched on is equal to a case, the statements following that case will execute until a break statement is reached.
When a break statement is reached, the switch terminates, and the flow of control jumps to the next line following the switch statement.
Not every case needs to contain a break. If no break appears, the flow of control will fall through to subsequent cases until a break is reached.
A switch statement can have an optional default case, which must appear at the end of the switch. The default case can be used for performing a task when none of the cases is true. No break is needed in the default case.
Flow Diagram
Example
Dev C Error Jump To Case Label Fpermissive
This would produce the following result −