JF Bastien 6e69db5a2d Document toolchain update policy
Summary:
Capture the current agreed-upon toolchain update policy based on the following
discussions:

  - LLVM dev meeting 2018 BoF "Migrating to C++14, and beyond!"
    llvm.org/devmtg/2018-10/talk-abstracts.html#bof3
  - A Short Policy Proposal Regarding Host Compilers
    lists.llvm.org/pipermail/llvm-dev/2018-May/123238.html
  - Using C++14 code in LLVM (2018)
    lists.llvm.org/pipermail/llvm-dev/2018-May/123182.html
  - Using C++14 code in LLVM (2017)
    lists.llvm.org/pipermail/llvm-dev/2017-October/118673.html
  - Using C++14 code in LLVM (2016)
    lists.llvm.org/pipermail/llvm-dev/2016-October/105483.html
  - Document and Enforce new Host Compiler Policy
    llvm.org/D47073
  - Require GCC 5.1 and LLVM 3.5 at a minimum
    llvm.org/D46723

Subscribers: jkorous, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D56819

llvm-svn: 351765
2019-01-21 23:53:52 +00:00
..
2018-01-12 21:42:39 +00:00
2018-11-27 18:57:43 +00:00
2018-05-14 12:53:11 +00:00
2019-01-17 00:31:35 +00:00
2019-01-16 10:57:02 +00:00
2017-02-07 20:36:03 +00:00
2018-08-21 21:00:54 +00:00
2017-04-03 18:21:50 +00:00
2018-08-18 20:17:19 +00:00
2017-06-24 20:13:32 +00:00
2018-07-26 04:44:31 +00:00

LLVM Documentation
==================

LLVM's documentation is written in reStructuredText, a lightweight
plaintext markup language (file extension `.rst`). While the
reStructuredText documentation should be quite readable in source form, it
is mostly meant to be processed by the Sphinx documentation generation
system to create HTML pages which are hosted on <http://llvm.org/docs/> and
updated after every commit. Manpage output is also supported, see below.

If you instead would like to generate and view the HTML locally, install
Sphinx <http://sphinx-doc.org/> and then do:

    cd <build-dir>
    cmake -DLLVM_ENABLE_SPHINX=true -DSPHINX_OUTPUT_HTML=true <src-dir>
    make -j3 docs-llvm-html
    $BROWSER <build-dir>/docs//html/index.html

The mapping between reStructuredText files and generated documentation is
`docs/Foo.rst` <-> `<build-dir>/docs//html/Foo.html` <-> `http://llvm.org/docs/Foo.html`.

If you are interested in writing new documentation, you will want to read
`SphinxQuickstartTemplate.rst` which will get you writing documentation
very fast and includes examples of the most important reStructuredText
markup syntax.

Manpage Output
===============

Building the manpages is similar to building the HTML documentation. The
primary difference is to use the `man` makefile target, instead of the
default (which is `html`). Sphinx then produces the man pages in the
directory `<build-dir>/docs/man/`.

    cd <build-dir>
    cmake -DLLVM_ENABLE_SPHINX=true -DSPHINX_OUTPUT_MAN=true <src-dir>
    make -j3 docs-llvm-man
    man -l >build-dir>/docs/man/FileCheck.1

The correspondence between .rst files and man pages is
`docs/CommandGuide/Foo.rst` <-> `<build-dir>/docs//man/Foo.1`.
These .rst files are also included during HTML generation so they are also
viewable online (as noted above) at e.g.
`http://llvm.org/docs/CommandGuide/Foo.html`.

Checking links
==============

The reachability of external links in the documentation can be checked by
running:

    cd docs/
    make -f Makefile.sphinx linkcheck

Doxygen page Output
==============

Install doxygen <http://www.stack.nl/~dimitri/doxygen/download.html> and dot2tex <https://dot2tex.readthedocs.io/en/latest>.

    cd <build-dir>
    cmake -DLLVM_ENABLE_DOXYGEN=On <llvm-top-src-dir>
    make doxygen-llvm # for LLVM docs
    make doxygen-clang # for clang docs

It will generate html in
    
    <build-dir>/docs/doxygen/html # for LLVM docs
    <build-dir>/tools/clang/docs/doxygen/html # for clang docs