5.7.6.1 Eliminate-unused-debug-symbols Option
The -feliminate-unused-debug-symbols
option eliminates the debug information
associated with any C/C++ symbol that has not been used in the program. This is also the
default action if no option has been specified. Eliminating this information will reduce
the size and load time of output files.
Use the -fno-eliminate-unused-debug-symbols
form of this option if you
want debug information generated for all symbols.