gas: Use the directory name in .file 0
DWARF5 allows .file 0 to take an optional directory name. Set the entry
0 of the directory table to the directory name in .file 0.
PR gas/28266
* dwarf2dbg.c (get_directory_table_entry): Add an argument for
the directory name in .file 0 and use it, instead of PWD.
(allocate_filenum): Pass NULL to get_directory_table_entry.
(allocate_filename_to_slot): Pass the incoming dirname to
get_directory_table_entry.
* testsuite/gas/elf/dwarf-5-file0-2.d: New file.
* testsuite/gas/elf/dwarf-5-file0-2.s: Likewise.
* testsuite/gas/elf/elf.exp: Run dwarf-5-file0-2.
4 files changed
