3.4.1.7 Symbol Table Listing Option

The -as form of this option requests a symbol table listing. The following example shows a listing that was generated using the -as command line option. Note that both defined and undefined symbols are listed.
GAS LISTING example.s 			page 1
DEFINED SYMBOLS
*ABS*:00000000 src\example.c
example.s:18     .text:00000000 main
*COM*:00000004 testval
UNDEFINED SYMBOLS
bar