From b48447a1d603a6609b9d6735fda6f875266237c8 Mon Sep 17 00:00:00 2001
From: Jonas Devlieghere <jonas@devlieghere.com>
Date: Wed, 16 May 2018 10:23:25 +0000
Subject: [PATCH] [diagtool] Add diagtool to install target.

Although not very well known, diagtool is an incredibly convenient
utility for dealing with diagnostics.
Particularly useful are the "tree" and "show-enabled" commands:

 - The former prints the hierarchy of diagnostic (warning) flags and
   which of them are enabled by default.
 - The latter can be used to replace an invocation to clang and will
   print which diagnostics are disabled, warnings or errors.
   For instance: `diagtool show-enabled -Wall -Werror /tmp/test.c` will
   print that -Wunused-variable (warn_unused_variable) will be treated as
   an error.

This patch adds them to the install target so it gets shipped with the
LLVM release. It also adds a very basic man page and mentions this
change in the release notes.

Differential revision: https://reviews.llvm.org/D46694

llvm-svn: 332448
---
 clang/docs/CommandGuide/diagtool.rst | 52 ++++++++++++++++++++++++++++
 clang/docs/CommandGuide/index.rst    |  1 +
 clang/docs/ReleaseNotes.rst          |  5 +++
 clang/tools/diagtool/CMakeLists.txt  | 12 +++++++
 4 files changed, 70 insertions(+)
 create mode 100644 clang/docs/CommandGuide/diagtool.rst

diff --git a/clang/docs/CommandGuide/diagtool.rst b/clang/docs/CommandGuide/diagtool.rst
new file mode 100644
index 0000000000000..59417f71f69d7
--- /dev/null
+++ b/clang/docs/CommandGuide/diagtool.rst
@@ -0,0 +1,52 @@
+diagtool - clang diagnostics tool
+=================================
+
+SYNOPSIS
+--------
+
+:program:`diagtool` *command* [*args*]
+
+DESCRIPTION
+-----------
+
+:program:`diagtool` is a combination of four tool for dealing with diagnostics in :program:`clang`.
+
+SUBCOMMANDS
+-----------
+
+:program:`diagtool` is separated into several subcommands each tailored to a
+different purpose. A brief summary of each command follows, with more detail in
+the sections that follow.
+
+  * :ref:`find_diagnostic_id` - Print the id of the given diagnostic.
+  * :ref:`list_warnings` - List warnings and their corresponding flags.
+  * :ref:`show_enabled` - Show which warnings are enabled for a given command line.
+  * :ref:`tree` - Show warning flags in a tree view.
+
+.. _find_diagnostic_id:
+
+find-diagnostic-id
+~~~~~~~~~~~~~~~~~~
+
+:program:`diagtool` find-diagnostic-id *diagnostic-name*
+
+.. _list_warnings:
+
+list-warnings
+~~~~~~~~~~~~~
+
+:program:`diagtool` list-warnings
+
+.. _show_enabled:
+
+show-enabled
+~~~~~~~~~~~~
+
+:program:`diagtool` show-enabled [*options*] *filename ...*
+
+.. _tree:
+
+tree
+~~~~
+
+:program:`diagtool` tree [*diagnostic-group*]
diff --git a/clang/docs/CommandGuide/index.rst b/clang/docs/CommandGuide/index.rst
index 826ed97119805..83a91182e9ca6 100644
--- a/clang/docs/CommandGuide/index.rst
+++ b/clang/docs/CommandGuide/index.rst
@@ -15,3 +15,4 @@ Basic Commands
    :maxdepth: 1
 
    clang
+   diagtool
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 93a258c6378fd..8414555464732 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -93,6 +93,11 @@ Non-comprehensive list of changes in this release
   behavior can be restored by setting ``-fclang-abi-compat`` to ``6`` or
   lower.
 
+- An existing tool named ``diagtool`` has been added to the release. As the
+  name suggests, it helps with dealing with diagnostics in ``clang``, such as
+  finding out the warning hierarchy, and which of them are enabled by default
+  or for a particular compiler invocation.
+
 - ...
 
 New Compiler Flags
diff --git a/clang/tools/diagtool/CMakeLists.txt b/clang/tools/diagtool/CMakeLists.txt
index 5193c241cd8e2..96d1c390249c3 100644
--- a/clang/tools/diagtool/CMakeLists.txt
+++ b/clang/tools/diagtool/CMakeLists.txt
@@ -17,3 +17,15 @@ target_link_libraries(diagtool
   clangBasic
   clangFrontend
   )
+
+if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
+  install(TARGETS diagtool
+    COMPONENT diagtool
+    RUNTIME DESTINATION bin)
+
+  if (NOT CMAKE_CONFIGURATION_TYPES)
+    add_llvm_install_targets(install-diagtool
+      DEPENDS diagtool
+      COMPONENT diagtool)
+  endif()
+endif()