/usr/lib/x86_64-linux-gnu/ is in libtexttools3-dev 2.0.7-2.
This file is owned by root:root, with mode 0o755.
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/usr/lib/x86_64-linux-gnu/libtexttools.a
/usr/lib/x86_64-linux-gnu/ada/
/usr/lib/x86_64-linux-gnu/ada/adalib/
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/gen_list.ali
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/controls.ali
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/common.ali
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/common-cpp.ali
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/windows.ali
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/strings.ali
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/os.ali
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/userio.ali
/usr/lib/x86_64-linux-gnu/ada/adalib/texttools/english.ali
/usr/lib/x86_64-linux-gnu/libtexttools.so