In C code, spell checking is supposed to occur in double quoted strings and comments. But a double quote char literal confuses the checker, as in the following:
case '"': somevar = othervar;
The s_string script complains that somevar and othervar are misspelled. It will have that behavior until the end of file, or the next occurrence of a double quote.
This is at least true on OSX aspell 0.60.6.1.