/usr/src/gcc-4.6/debian/libgcjGCJ-dev.overrides is in gcc-4.6-source 4.6.4-6ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1
libgcj@GCJ@-dev binary: library-not-linked-against-libc