/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/ is in libphobos-5-dev 5.5.0-12ubuntu1.
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/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/fenv.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/freebsd/
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/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/linux/
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/linux/linux.d
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/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/linux/termios.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/linux/tipc.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/locale.d
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/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/osx/socket.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/process.d
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/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/stddef.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/stdio.d
/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/c/stdlib.d
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/usr/lib/gcc/x86_64-linux-gnu/5/include/d/std/container/array.d
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