To change current line number and possibly the name of the current source file being preprocessed, which are tracked by the assembler preprocessor, with emitting a corresponding ‘line’ directive to the preprocessed output for subsequent interpreting by the assembler, use the ‘line’ directive of the assembler preprocessor. Additionally, information changed by the ‘line’ directive is used when generating error and note messages by the assembler preprocessor.
The directive must be placed on a separate line (after at least one whitespace character at the beginning of the line) and must be in one of the following formats:
line line_number line line_number, file_name
In the first case, the directive changes the number of the next line in the current source file to line_number. In the second case, the directive changes the number of the next line to line_number and the name of current source file to file_name. The value of file_name must be a (quoted) string literal.