llvm-symbolizer and llvm-addr2line allow to read addresses
from stdin, which makes them convenient to use in a context
where a large number of addresses should be resolved
(which may be too many to pass as command line arguments)
or not all addresses are known at the same time.
This patch adds a --addresses-from-stdin option to
llvm-gsymutil to allow the same.
You will need to specify what format the STDIN format needs to be. From reading to the code below it seems to be: