5.11.3 File Directive
The .file fileno
"filename"
directive assigns filenames to the .debug_line
file name table when emitting dwarf2 line-number
information. The fileno
operand should be a unique
positive integer to use as the index of the entry in the table. The
filename
operand is a C string literal.
The detail of filename
indices is
exposed to the user because the filename table is shared with the .debug_info
section of the dwarf2 debugging information, and thus the user
must know the exact indices that table entries will have.