Failure to specify function prototypes results in a function being implicitly defined. Without a function prototype, the compiler will assume the the correct number and type of parameters have been supplied to a function. This can result in undefined, and perhaps unintended behavior.
| Wiki Markup |
|---|
C99 removed implicit function declarations from the C language \[[ISO/IEC9899-1999|AA. C References#ISO/IEC 9899-1999]\]. However, compilers will typically allow compilation of programs that contain implicitly defined functions, although they will issue a warning. These warnings should be resolved \[[MSC00-A|MSC00-A. Compile cleanly at high warning levels]\], but they will not prevent program compilation.
Failure to specify function prototypes results in a function being implicitly defined. Without a function prototype, the compiler will assume the the correct number and type of parameters have been supplied to a function. This can result in undefined, and perhaps unintended behavior. Given this, functions should be declared with the appropriate function prototype. |
...