Controls the recognition of unreferenced variables.
#pragma warn_unusedvar on | off | reset
If you enable this pragma, the compiler issues a warning message when it encounters a variable you declare but do not use.
This check helps you find variables that you either misspelled or did not use in your program. Listing: Unused Local Variables Example shows an example.
int error; void func(void) { int temp, errer; /* NOTE: errer is misspelled. */ error = do_something(); /* WARNING: temp and errer are unused. */ }
If you want to use this warning but need to declare a variable that you do not use, include the pragma unused, as in Listing: Suppressing Unused Variable Warnings.
void func(void) { int i, temp, error; #pragma unused (i, temp) /* Do not warn that i and temp */ error = do_something(); /* are not used */ }