/usr/src/gcc-6/debian/source.lintian-overrides.in is in gcc-6-source 6.4.0-17ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 | @SRC@ source: invalid-arch-string-in-source-relation
@SRC@ source: quilt-build-dep-but-no-series-file
# lintian can't handle (>= ${gcc:Version})
@SRC@ source: weak-library-dev-dependency
@SRC@ source: patch-file-present-but-not-mentioned-in-series
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