/* Source file current line is coming from. */
extern char *input_filename
;
/* Top-level source file. */
extern char *main_input_filename
;
/* Line number in current source file. */
/* Stream for reading from input file. */
/* Stack of currently pending input files.
The line member is not accurate for the innermost file on the stack. */
extern struct file_stack
*input_file_stack
;
/* Incremented on each change to input_file_stack. */
extern int input_file_stack_tick
;