ILE C/C++ Language Reference
An integer compile-time constant is a value
that is determined during compilation and cannot be changed at run
time. An integer compile-time constant expression is
an expression that is composed of constants and evaluated to a constant.
An integer constant expression is an expression that is composed
of only the following:
- literals
- enumerators
- const variables
- static data members of integral or enumeration types
- casts to integral types
- sizeof expressions, where the operand is not a variable
length array
The sizeof operator applied to a variable length array
type is evaluated at run time, and therefore is not a constant expression.
You must use an integer constant expression in the following situations:
- In the subscript declarator as the description of an array bound.
- After the keyword case in a switch statement.
- In an enumerator, as the numeric value of an enumeration constant.
- In a bit-field width specifier.
- In the preprocessor #if statement. (Enumeration
constants, address constants, and sizeof cannot be specified
in a preprocessor #if statement.)
Related information
[ Top of Page | Previous Page | Next Page | Contents |
Index ]