200 lines
7.0 KiB
ReStructuredText
200 lines
7.0 KiB
ReStructuredText
===================================
|
|
How To Setup Clang Tooling For LLVM
|
|
===================================
|
|
|
|
Clang Tooling provides infrastructure to write tools that need syntactic
|
|
and semantic information about a program. This term also relates to a set
|
|
of specific tools using this infrastructure (e.g. ``clang-check``). This
|
|
document provides information on how to set up and use Clang Tooling for
|
|
the LLVM source code.
|
|
|
|
Introduction
|
|
============
|
|
|
|
Clang Tooling needs a compilation database to figure out specific build
|
|
options for each file. Currently it can create a compilation database
|
|
from the ``compilation_commands.json`` file, generated by CMake. When
|
|
invoking clang tools, you can either specify a path to a build directory
|
|
using a command line parameter ``-p`` or let Clang Tooling find this
|
|
file in your source tree. In either case you need to configure your
|
|
build using CMake to use clang tools.
|
|
|
|
Setup Clang Tooling Using CMake and Make
|
|
========================================
|
|
|
|
If you intend to use make to build LLVM, you should have CMake 2.8.6 or
|
|
later installed (can be found `here <http://cmake.org>`_).
|
|
|
|
First, you need to generate Makefiles for LLVM with CMake. You need to
|
|
make a build directory and run CMake from it:
|
|
|
|
.. code-block:: console
|
|
|
|
$ mkdir your/build/directory
|
|
$ cd your/build/directory
|
|
$ cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=ON path/to/llvm/sources
|
|
|
|
If you want to use clang instead of GCC, you can add
|
|
``-DCMAKE_C_COMPILER=/path/to/clang -DCMAKE_CXX_COMPILER=/path/to/clang++``.
|
|
You can also use ``ccmake``, which provides a curses interface to configure
|
|
CMake variables for lazy people.
|
|
|
|
As a result, the new ``compile_commands.json`` file should appear in the
|
|
current directory. You should link it to the LLVM source tree so that
|
|
Clang Tooling is able to use it:
|
|
|
|
.. code-block:: console
|
|
|
|
$ ln -s $PWD/compile_commands.json path/to/llvm/source/
|
|
|
|
Now you are ready to build and test LLVM using make:
|
|
|
|
.. code-block:: console
|
|
|
|
$ make check-all
|
|
|
|
Using Clang Tools
|
|
=================
|
|
|
|
After you completed the previous steps, you are ready to run clang tools. If
|
|
you have a recent clang installed, you should have ``clang-check`` in
|
|
``$PATH``. Try to run it on any ``.cpp`` file inside the LLVM source tree:
|
|
|
|
.. code-block:: console
|
|
|
|
$ clang-check tools/clang/lib/Tooling/CompilationDatabase.cpp
|
|
|
|
If you're using vim, it's convenient to have clang-check integrated. Put
|
|
this into your ``.vimrc``:
|
|
|
|
::
|
|
|
|
function! ClangCheckImpl(cmd)
|
|
if &autowrite | wall | endif
|
|
echo "Running " . a:cmd . " ..."
|
|
let l:output = system(a:cmd)
|
|
cexpr l:output
|
|
cwindow
|
|
let w:quickfix_title = a:cmd
|
|
if v:shell_error != 0
|
|
cc
|
|
endif
|
|
let g:clang_check_last_cmd = a:cmd
|
|
endfunction
|
|
|
|
function! ClangCheck()
|
|
let l:filename = expand('%')
|
|
if l:filename =~ '\.\(cpp\|cxx\|cc\|c\)$'
|
|
call ClangCheckImpl("clang-check " . l:filename)
|
|
elseif exists("g:clang_check_last_cmd")
|
|
call ClangCheckImpl(g:clang_check_last_cmd)
|
|
else
|
|
echo "Can't detect file's compilation arguments and no previous clang-check invocation!"
|
|
endif
|
|
endfunction
|
|
|
|
nmap <silent> <F5> :call ClangCheck()<CR><CR>
|
|
|
|
When editing a .cpp/.cxx/.cc/.c file, hit F5 to reparse the file. In
|
|
case the current file has a different extension (for example, .h), F5
|
|
will re-run the last clang-check invocation made from this vim instance
|
|
(if any). The output will go into the error window, which is opened
|
|
automatically when clang-check finds errors, and can be re-opened with
|
|
``:cope``.
|
|
|
|
Other ``clang-check`` options that can be useful when working with clang
|
|
AST:
|
|
|
|
* ``-ast-print`` --- Build ASTs and then pretty-print them.
|
|
* ``-ast-dump`` --- Build ASTs and then debug dump them.
|
|
* ``-ast-dump-filter=<string>`` --- Use with ``-ast-dump`` or ``-ast-print`` to
|
|
dump/print only AST declaration nodes having a certain substring in a
|
|
qualified name. Use ``-ast-list`` to list all filterable declaration node
|
|
names.
|
|
* ``-ast-list`` --- Build ASTs and print the list of declaration node qualified
|
|
names.
|
|
|
|
Examples:
|
|
|
|
.. code-block:: console
|
|
|
|
$ clang-check tools/clang/tools/clang-check/ClangCheck.cpp -ast-dump -ast-dump-filter ActionFactory::newASTConsumer
|
|
Processing: tools/clang/tools/clang-check/ClangCheck.cpp.
|
|
Dumping ::ActionFactory::newASTConsumer:
|
|
clang::ASTConsumer *newASTConsumer() (CompoundStmt 0x44da290 </home/alexfh/local/llvm/tools/clang/tools/clang-check/ClangCheck.cpp:64:40, line:72:3>
|
|
(IfStmt 0x44d97c8 <line:65:5, line:66:45>
|
|
<<<NULL>>>
|
|
(ImplicitCastExpr 0x44d96d0 <line:65:9> '_Bool':'_Bool' <UserDefinedConversion>
|
|
...
|
|
$ clang-check tools/clang/tools/clang-check/ClangCheck.cpp -ast-print -ast-dump-filter ActionFactory::newASTConsumer
|
|
Processing: tools/clang/tools/clang-check/ClangCheck.cpp.
|
|
Printing <anonymous namespace>::ActionFactory::newASTConsumer:
|
|
clang::ASTConsumer *newASTConsumer() {
|
|
if (this->ASTList.operator _Bool())
|
|
return clang::CreateASTDeclNodeLister();
|
|
if (this->ASTDump.operator _Bool())
|
|
return clang::CreateASTDumper(this->ASTDumpFilter);
|
|
if (this->ASTPrint.operator _Bool())
|
|
return clang::CreateASTPrinter(&llvm::outs(), this->ASTDumpFilter);
|
|
return new clang::ASTConsumer();
|
|
}
|
|
|
|
(Experimental) Using Ninja Build System
|
|
=======================================
|
|
|
|
Optionally you can use the `Ninja <https://github.com/martine/ninja>`_
|
|
build system instead of make. It is aimed at making your builds faster.
|
|
Currently this step will require building Ninja from sources.
|
|
|
|
To take advantage of using Clang Tools along with Ninja build you need
|
|
at least CMake 2.8.9.
|
|
|
|
Clone the Ninja git repository and build Ninja from sources:
|
|
|
|
.. code-block:: console
|
|
|
|
$ git clone git://github.com/martine/ninja.git
|
|
$ cd ninja/
|
|
$ ./bootstrap.py
|
|
|
|
This will result in a single binary ``ninja`` in the current directory.
|
|
It doesn't require installation and can just be copied to any location
|
|
inside ``$PATH``, say ``/usr/local/bin/``:
|
|
|
|
.. code-block:: console
|
|
|
|
$ sudo cp ninja /usr/local/bin/
|
|
$ sudo chmod a+rx /usr/local/bin/ninja
|
|
|
|
After doing all of this, you'll need to generate Ninja build files for
|
|
LLVM with CMake. You need to make a build directory and run CMake from
|
|
it:
|
|
|
|
.. code-block:: console
|
|
|
|
$ mkdir your/build/directory
|
|
$ cd your/build/directory
|
|
$ cmake -G Ninja -DCMAKE_EXPORT_COMPILE_COMMANDS=ON path/to/llvm/sources
|
|
|
|
If you want to use clang instead of GCC, you can add
|
|
``-DCMAKE_C_COMPILER=/path/to/clang -DCMAKE_CXX_COMPILER=/path/to/clang++``.
|
|
You can also use ``ccmake``, which provides a curses interface to configure
|
|
CMake variables in an interactive manner.
|
|
|
|
As a result, the new ``compile_commands.json`` file should appear in the
|
|
current directory. You should link it to the LLVM source tree so that
|
|
Clang Tooling is able to use it:
|
|
|
|
.. code-block:: console
|
|
|
|
$ ln -s $PWD/compile_commands.json path/to/llvm/source/
|
|
|
|
Now you are ready to build and test LLVM using Ninja:
|
|
|
|
.. code-block:: console
|
|
|
|
$ ninja check-all
|
|
|
|
Other target names can be used in the same way as with make.
|
|
|