/usr/src/gcc-8/debian/libitm.symbols is in gcc-8-source 8-20180414-1ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | libitm.so.1 #PACKAGE# #MINVER#
(symver)LIBITM_1.0 4.7
(symver)LIBITM_1.1 6
|