8 Fullbuild requires running headergen, which is a python program that depends on
9 pyyaml. The minimum versions are listed on the :ref:`header_generation`
10 page, as well as additional information.
12 The *fullbuild* mode of LLVM's libc is the mode in which it is to be used as
13 the only libc (as opposed to the :ref:`overlay_mode` in which it is used along
14 with the system libc.) In order to use it as the only libc, one will have to
15 build and install not only the static archives like ``libc.a`` from LLVM's libc,
16 but also the start-up objects like ``crt1.o`` and the public headers.
18 The full libc build can be of two types: