rtags | ac-rtags | company-rtags | flycheck-rtags | helm-rtags | ivy-rtags |
---|---|---|---|---|---|
Introduction
RTags is a client/server application that indexes C/C++ code and keeps a persistent file-based database of references, declarations, definitions, symbolnames etc. There’s also limited support for ObjC/ObjC++. It allows you to find symbols by name (including nested class and namespace scope). Most importantly we give you proper follow-symbol and find-references support. We also have neat little things like rename-symbol, integration with clang’s “fixits” (http://clang.llvm.org/diagnostics.html). We also integrate with flymake using clang’s vastly superior errors and warnings. Since RTags constantly will reindex “dirty” files you get live updates of compiler errors and warnings. Since we already know how to compile your sources we have a way to quickly bring up the preprocessed output of the current source file in a buffer.
While existing taggers like gnu global, cscope, etags, ctags etc do a decent job for C they often fall a little bit short for C++. With its incredible lexical complexity, parsing C++ is an incredibly hard task and we make no bones about the fact that the only reason we are able to improve on the current tools is because of clang (http://clang.llvm.org/). RTags is named RTags in recognition of Roberto Raggi on whose C++ parser we intended to base this project but he assured us clang was the way to go. The name stuck though.
TLDR Quickstart
Build RTags
git clone --recursive https://github.com/Andersbakken/rtags.git
cd rtags
cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=1 .
make
Start the RTags daemon (rdm
)
./bin/rdm &
Index the RTags project, and wait until rdm
is silent
./bin/rc -J .
Open source file in emacs
emacs +73:34 src/rdm.cpp
Load rtags.el
M-: (load-file "rtags.el") RET
Insure rc
can be found
M-: set-variable RET rtags-path RET "../bin" RET
Call rtags-find-symbol-at-point
M-x rtags-find-symbol-at-point RET
Your location is now on the definition of Server::instance()
Installing RTags
Prerequisites
There are a few prerequisites you need to have in order to build RTags
LLVM/Clang
>= 3.3On Linux you may be able to use your distribution package manager to install this. On OS X you can use Homebrew or possibly other package managers, though see below for details if you plan to tag projects that use C++11 features (such as RTags itself). Alternatively you can grab the sources from llvm.org and build it yourself.
GCC/Clang
>= 4.7/3.2A modern compiler to build RTags. RTags makes extensive use of C++11 features such as variadic templates and threading utility classes from the C++ standard library.
cmake
>= 2.8The meta-built system used by RTags.
emacs
>= 24.3 is recommendedRTags might very well work with much older
emacs
versions but the oldest version we have tested with is 23.4.1. There’s no particular effort made to support older versions, but patches that make it work are welcome. Having said that, completion (ac, company) as well as Flycheck integration only works, and has been tested withemacs
>= 24.3.NOTE: Emacs is no real prerequisite. That implies you can compile RTags without
emacs
installed. This may be of interest to you, if you want use RTags as back-end for a different editor like vim, see section Support for other editors. You explicitly can tellcmake
to ignore the elisp files by passing-DRTAGS_NO_ELISP_FILES=1
tocmake
.
Optional
pkg-config
andbash-completion
RTags comes with bash completion support. If you want the bash completion files to be installed, you either have to make sure that
pkg-config
andbash-completion
package is installed or you can manually force the installation by setting the variableFORCE_BASH_COMPLETION_INSTALLATION
toTRUE
orON
.The default installation path is
CMAKE_INSTALL_PREFIX/share/bash-completion/completions
. You can adjust the path with thecmake
variableBASH_COMPLETION_COMPLATIONSDIR
variable. However, if the bash completions files are not installed in the default completion path, i.e./usr/share/bash-completion/completions
on GNU/Linux, you have to make sure the RTags bash completion file gets sourced to get completion support.lua
version >= 5.3TODO(Andersbakken): Add some notes why we optionally require Lua, whats the purpose of it.
If your system does not provide a suitable version you can download Lua from here. We recommend downloading the pre-built binaries. If you have compiled Lua from scratch (the build will only create an archive
liblua.a
and no shared library) or you have installed the headers/library to a non standard place you need to tellcmake
where the headers/library is located.E.g.
cmake -DLUA_INCLUDE_DIR=/opt/lua/include -DLUA_LIBRARY=/opt/lua/lib/liblua.a # or liblua53.so or liblua53.a if you have downloaded, e.g. lua-5.3.2 binaries cmake -DLUA_INCLUDE_DIR=/opt/lua/include -DLUA_LIBRARY=/opt/lua/lib/liblua53.so
ZLIB
OpenSSL
C++11 on OS X
If you plan to tag projects using C++11 features on OS X then you’ll need a libclang linked with LLVM’s libc++. For LLVM 3.9 the following works:
brew install llvm --with-libcxx --with-clang --without-assertions --with-rtti
Note that unless you link llvm
brew link llvm
You’ll likely have to tell cmake where to find llvm-config.
E.g.
$ PATH=/usr/local/Cellar/llvm/3.9.1/bin/:$PATH cmake /path/to/rtags
$ make
or you can install clang and llvm from mac ports
sudo port install clang-3.5
Building RTags
- Get the code
To build RTags, you need to checkout RTags and the repository’s sub-modules, this can be done in one step. After that, you need to run
cmake
,make
andmake install
, in that order.git clone --recursive https://github.com/Andersbakken/rtags.git
You can also download the sources from here:
https://andersbakken.github.io/rtags-releases/rtags-2.9.tar.bz2
or
https://andersbakken.github.io/rtags-releases/rtags-2.9.tar.gz
- Building RTags
We recommend building in a separate directory to keep the build files separate from the source, but you can run
cmake
in the source tree if you prefer.cd rtags mkdir build cd build cmake .. make make install
TIP: You can run
ccmake
(CMake with an ncurses UI) instead ofcmake
to interactively configure the RTags build. - Elpa
You can install the elisp part of RTags using package.el if you add melpa to your sources list.
Once you have emacs installed from melpa you can use the elisp to build the c++ parts of RTags. You still need to have a working compiler, libclang and cmake installed.
To use:
M-x rtags-install <ret>
You may have to set additional arguments to cmake for this work. E.g.
M-: (rtags-install nil "-DLIBCLANG_LLVM_CONFIG_EXECUTABLE=/usr/local//Cellar/llvm/4.0.0/bin/llvm-config") <ret>
Finding clang
Use Your System’s version
Unless you define RTAGS_BUILD_CLANG in cmake (or configure), the build system will try to locate the required llvm/clang libraries and options automatically from what is installed on your system.
RTags needs three pieces of information about libclang
. All of these can be
provided to cmake
by way of an environment variable or a cmake
variable. If
not provided we will try to find llvm-config
and interrogate it for the
information. You can tell RTags which llvm-config
to use like this:
LIBCLANG_LLVM_CONFIG_EXECUTABLE=/path/to/llvm-config cmake .
or
cmake -DLIBCLANG_LLVM_CONFIG_EXECUTABLE=/path/to/llvm-config .
If you don’t, we will look for variations of the llvm-config
executable name
in your $PATH
. If llvm is installed at a different place, you could set the
cmake variable CMAKE_PREFIX_PATH
to the install prefix path of llvm.
The three things we need are:
LIBCLANG_CXXFLAGS
Usually something like this:
$ llvm-config --cxxflags # Max OS X -I/usr/local/Cellar/llvm36/3.6.0/lib/llvm-3.6/include -DNDEBUG -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -O3 -std=c++11 -fvisibility-inlines-hidden -fno-exceptions -fno-common -Woverloaded-virtual -Wcast-qual # Fedora 23 64 bit -I/usr/include -DNDEBUG -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -O3 -std=c++11 -fvisibility-inlines-hidden -fno-exceptions -fno-common -Woverloaded-virtual -Wcast-qual
LIBCLANG_LIBDIR
Usually something like this:
$ llvm-config --libdir # Mac OS X /usr/local/Cellar/llvm36/3.6.0/lib/llvm-3.6/lib # Fedora 23 64 bit /usr/lib64/llvm
We need this to locate clang’s system headers, and we will assume that they are located in:
${LIBCLANG_LIBDIR}/clang/CLANG_VERSION_STRING/include (/usr/local/Cellar/llvm36/3.6.0/lib/llvm-3.6/lib/clang/3.6.0/include)
. There should be headers like stdarg.h and limits.h in this directory.LIBCLANG_LIBRARIES
Usually something like this:
# Mac OS X /usr/local/Cellar/llvm36/3.6.0/lib/llvm-3.6/lib/libclang.so # Fedora 23 64 bit /usr/lib64/llvm/libclang.so
Unless otherwise specified, we will try to find the clang library using
cmake
’sfind_library
feature and/or assuming that they there will be a libclang.(so|dylib) in${LIBCLANG_LIBDIR}
Like with LIBCLANG_LLVM_CONFIG_EXECUTABLE
these variables can be overwritten
as a cmake
variable (cmake -DLIBCLANG_LIBDIR =...)
or an environment variable
(LIBCLANG_LIBDIR =... cmake)
Let the Build System Download and Compile LLVM/Clang
By default, cmake searches for a system libclang. If you want it to download and build the required llvm/clang libraries, either call cmake with -DRTAGS_BUILD_CLANG=1 or configure with –build-clang
Note that if you use ninja to build RTags you might run into the following error:
ninja: error: '/usr/local/rtags-llvmclang/lib/libclang.dylib', needed by 'bin/rdm', missing and no known rule to make it
In that case you need to do this:
ninja llvmclang && ninja && ninja install
RTags uses C++11 features, and requires a relatively new compiler. GCC version >= 4.8 or clang >= 3.2 should work.
Setup
rdm
runs in the background and monitors all your indexed files for changes,
and reindexes when a source file or one of its dependencies is modified. Since
clang is a fully compliant compiler it needs specific information about how
your sources are compiled to be able to properly index them. This is done
through telling rdm
about the compile line like this:
rc -c gcc -I... -fsomeflag -c foobar.c
rc -J /path/to/a/directory/containing/compile_commands.json
You can generate a compile_commands.json with various different tools, one might fit better than the other, depending on your project build system.
- ninja
ninja -t compdb cxx cc > compile_commands.json rc -J
With
ninja
it’s also possible to pipe the commands directly torc
.ninja -t commands | rc -c - # Parse commands for a specific target only ninja -t commands rdm | rc -c -
cmake
cmake
can generate a compile_commands.json file as well.cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=1 . rc -J
- Bear
For other projects you can use
bear
to generate a compile_commands.json file. However, if you are cross-compiling you probably need to adjust the command entries in the compile_commands.json file to match the correct compiler. Furthermore, make sure you clean your project before invokingbear
.make clean bear make rc -J # Parse commands for a specific target only make clean bear make rdm rc -J
make
You can ask
make
to only print the recipes without actually doing something. This way may be perfectly fine for not too complex Makefiles.make clean make -nk | rc -c -
There are very likely similar things you can do with other build systems that we’re unfamiliar with, please let us know if you do.
- A different approach to get your files indexed is the man-in-the-middle
This can be done like this:
ln -s /path/to/rtags/bin/gcc-rtags-wrapper.sh /somewhere/that/is/in/your/path/before/usr/bin/gcc ln -s /path/to/rtags/bin/gcc-rtags-wrapper.sh /somewhere/that/is/in/your/path/before/usr/bin/c++ ln -s /path/to/rtags/bin/gcc-rtags-wrapper.sh /somewhere/that/is/in/your/path/before/usr/bin/cc ln -s /path/to/rtags/bin/gcc-rtags-wrapper.sh /somewhere/that/is/in/your/path/before/usr/bin/g++
E.g.
$ which -a gcc | xargs file /home/abakken/bin/gcc: symbolic link to `/home/abakken/dev/rtags/bin/gcc-rtags-wrapper.sh' /usr/bin/gcc: symbolic link to `gcc-4.7'
Now every time you compile a file with
which gcc
rc
will get its grubby hands all over your command line and make sure RTags knows about it.
RTags will group source files into projects based on some heuristics.
Essentially it will look for certain files/dirs (like
configure/CMakeLists.txt/scons.1/.git) etc to try to determine the likely
project root for each source file. For generated source files that end up in
the build directory we try to find the source root based on similar heuristics
around config.status/CMakeCache.txt etc. Usually this works out reasonably
well. If it doesn’t for you, you can pass --project-root
/path/to/the/project/root
to rc
.
RTags only gives you information about current project when you ask for things by name. You can explicitly change the current project using:
rc -w foobar
We try to do it automatically for you by passing along information about the
current buffer when we call rc
from elisp so that rdm
can update its
current project on demand.
RTags keeps a cache of indexed data so you don’t have to reindex everything if you restart it.
The location of this data is by default ~/.rtags
but can be overridden by
passing --data-dir /other/dir
to rdm
or putting something like this in
your ~/.rdmrc:
$ cat ~/.rdmrc --data-dir=/other/dir
launchd
(Mac OS X)
Integration with On Mac OS X, you can set rdm
can be run on demand, on your behalf, by
launchd
, and have it exit cleanly after a period of inactivity. The easiest
way to do this is with Homebrew:
brew services start rtags
You can also do it manually using the following steps:
- Create a file, e.g., in emacs, with the following contents:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>Label</key> <string>com.andersbakken.rtags.agent</string> <key>ProgramArguments</key> <array> <string>sh</string> <string>-c</string> <string>$RDM -v --launchd --inactivity-timeout 300 --log-file ~/Library/Logs/rtags.launchd.log</string> </array> <key>Sockets</key> <dict> <key>Listener</key> <dict> <key>SockPathName</key> <string>$HOME/.rdm</string> </dict> </dict> </dict> </plist>
- Replace
$HOME
with the absolute path to your home folder. Replace$RDM
with the path to your copy ofrdm
, and add any command line parameters you might usually use.(The
SockPathName
entry relates to the name of the domain socket thatrdm
uses. The settings above are for the default value; if your command line options direct it to use some other name, please modify it to suit. Unfortunatelylaunchd
’s configuration files are a bit naff, so you’ll have to repeat yourself.) - Save the result as
~/Library/LaunchAgents/com.andersbakken.rtags.agent.plist
. - Run the following command from the terminal:
launchctl load ~/Library/LaunchAgents/com.andersbakken.rtags.agent.plist
(This will happen automatically next time you log back in.)
- Try using RTags, and you should find
rdm
will spring into life!
Notes
rdm
will automatically quit after 5 minutes of inactivity (this is what the--inactivity-timeout 300
command line option is for), so it won’t stick around hogging memory. Butlaunchd
will still be watching its socket for activity, and will relaunch it if necessary.- You can watch
launchd
’s logging by tailing~/Library/Logs/rtags.launchd.log
.
systemd
(GNU Linux)
Integration with On GNU/Linux distributions based on the systemd
service manager, rdm
can
also be socket acivated.
- Add the following to
~/.config/systemd/user/rdm.socket
[Unit] Description=RTags daemon socket [Socket] ListenStream=%t/rdm.socket [Install] WantedBy=default.target
- Add the following to
~/.config/systemd/user/rdm.service
[Unit] Description=RTags daemon Requires=rdm.socket [Service] Type=simple ExecStart=$RDM -v --inactivity-timeout 300 --log-flush
- Replace
$RDM
with the path to your copy ofrdm
, and add any command line parameters you might usually use.You have to use absolute paths here.
%h
is expanded to your home directory. Environment variables are not expanded inside strings. - Run the following command from the terminal:
systemctl --user enable rdm.socket systemctl --user start rdm.socket
Systemd
will create therdm
socket automatically.
Usage
Now that your files are indexed you can start using RTags. Normally you
would do this from your editor but the way to extract this information from
rdm
is to use the command line tool rc
.
E.g.
$ rdm & $ ninja -t commands | rc -c $ rc --follow-location Job.cpp:20:10 /home/abakken/dev/rtags/src/Job.h:10:18 List<RegExp> *mPathFiltersRegExp;
A location has the format of file:line:column.
For Emacs we maintain a set of elisp bindings that allows you to control RTags from your editor. There are projects that provide integration for other editors out there.
Vim: https://github.com/lyuts/vim-rtags and https://github.com/shaneharper/vim-rtags
Sublime Text: https://github.com/rampage644/sublime-rtags
Atom: https://github.com/artagnon/atomic-rtags, https://github.com/rajendrant/atom-rtags and https://github.com/sphaerophoria/atom-rtags-plus
rc
has a vast number of commands and options and we intend to write a man
page at some point. Most users will have limited interest in ever calling them
manually and would rather just use the interactive elisp functions.
Elisp
Functions
(rtags-start-process-unless-running)
Start the rdm
process unless the process is already running. You may create
hook to automatically call this function upon entering, e.g. c-mode or
c++mode.
E.g.
(add-hook 'c-mode-hook 'rtags-start-process-unless-running)
(add-hook 'c++-mode-hook 'rtags-start-process-unless-running)
(add-hook 'objc-mode-hook 'rtags-start-process-unless-running)
(rtags-restart-process)
Restart the rdm
process.
(rtags-find-symbol-at-point)
Follow symbol under cursor. For references this goes to the definition (or
declaration if no definition is known of the symbol. For declarations it goes
to the definition and vice versa. For definitions of variables/parameters with
constructors it goes to the constructor in question. If you pass a prefix
argument, limit to current source file, if you pass a prefix argument and have
narrowed the current file, limit to the narrowed region. This prefix argument
is the same for: rtags-find-references-at-point
, rtags-find-symbol
,
rtags-find-references
(rtags-find-references-at-point)
Find all references to symbol under cursor. If symbol is itself a reference it will find all references to the referenced symbol
(rtags-find-symbol)
Prompt for name of symbol to go to. Imagine the following code:
namespace N
{
class C
{
public:
int func(int);
};
};
using namespace N;
int C::func(int val)
{
return val * 2;
}
int N::C::func(int) will now be accessible by the following names:
- func
- func(int)
- C::func(int)
- C::func
- N::C::func(int)
- N::C::func
(rtags-find-references)
Prompt for name of symbol to find references to. Same as above but find references to symbol rather than declarations and definitions.
(rtags-diagnostics)
Start an async process in a buffer to receive warnings/errors from clang whenever a file gets reindexed. It integrates with flymake to put highlighting on code with warnings and errors
(rtags-enable-standard-keybindings)
Sets up a ton of standard keybindings under C-c r. If you pass a mode to the function it will set it up on that mode, otherwise it will use c-mode-base-map). You can choose a different prefix than C-c r like this:
(rtags-enable-standard-keybindings c-mode-base-map "\C-xr")
(rtags-find-file)
Lets you jump to file by name (partial or full, concept kinda stolen from gtags.el) with completion in the project. This includes all files under what we determine to be the root of the project, not just source files.
(rtags-find-virtuals-at-point)
For virtual functions, show the various reimplementations of the function at point
(rtags-fixit)
Apply clang’s automatic fixits in current file. If you pass a prefix arg use ediff to apply it. See (http://clang.llvm.org/diagnostics.html) for more info.
(rtags-imenu)
Provides an ido-based imenu like interface to a subset of the symbols in the current file. Note that it does not actually use imenu infrastructure.
(rtags-location-stack-back)
(rtags-location-stack-forward)
Whenever RTags jumps somewhere it pushes a location onto its stack. Jump back and forward in this stack
(rtags-next-match)
(rtags-previous-match)
For functions that return more than one match, jump to the next/previous one.
(rtags-preprocess-file)
Preprocess current file according to known C(XX)Flags and show the result in a buffer. If region is active only display the preprocessed output for that region.
(rtags-print-symbol-info)
Print some info about symbol under cursor
(rtags-symbol-type)
Print the type of the symbol under cursor.
(rtags-print-dependencies)
Open a buffer showing files that depend on current file/files that current file depends on.
(rtags-print-enum-value-at-point)
Print integral value of enum value at point
(rtags-quit-rdm)
Shut down rdm
(rtags-rename-symbol)
Rename symbol under cursor. Make sure all files are saved and fully indexed before using.
(rtags-reparse-file)
Explicitly trigger a reparse of current file. Mostly for debugging. Unless we have bugs it should not be necessary.
(rtags-show-rtags-buffer)
Switch to *RTags*
buffer. This is the buffer where a number of functions
display their alternatives when they have more than one match.
(rtags-include-file)
Insert selected or entered include, e.g. “string.h”/<string.h> in current
buffer, either at the top, after the first include statement or with prefix
argument (C-u
) at current point.
(rtags-get-include-file-for-symbol)
Insert include for entered symbol or symbol under courser in current buffer,
either at the top, after the first include statement or with prefix argument
(C-u
) at current point.
Variables
rtags-path
Path to rc/rdm
if they’re not in $PATH
.
rtags-jump-to-first-match
Similar to compilation-auto-jump-to-first-error
. Whether to jump to the
first match automatically when there’s more than one.
rtags-find-file-case-insensitive
Whether to match files case-insensitively
rtags-find-file-prefer-exact-match
Whether to exclude partial matches for file names when an exact match is
found. E.g. /foobar.cpp
/bar.cpp
If rtags-find-file-prefer-exact-match
is t
a query for bar.cpp
would only return /bar.cpp
, otherwise both
foobar.cpp
and bar.cpp
would be returned.
Fall back to other taggers
You can do something like the following to fall back to e.g. gtags if RTags doesn’t have a certain project indexed:
(defun use-rtags (&optional useFileManager)
(and (rtags-executable-find "rc")
(cond ((not (gtags-get-rootpath)) t)
((and (not (eq major-mode 'c++-mode))
(not (eq major-mode 'c-mode))) (rtags-has-filemanager))
(useFileManager (rtags-has-filemanager))
(t (rtags-is-indexed)))))
(defun tags-find-symbol-at-point (&optional prefix)
(interactive "P")
(if (and (not (rtags-find-symbol-at-point prefix)) rtags-last-request-not-indexed)
(gtags-find-tag)))
(defun tags-find-references-at-point (&optional prefix)
(interactive "P")
(if (and (not (rtags-find-references-at-point prefix)) rtags-last-request-not-indexed)
(gtags-find-rtag)))
(defun tags-find-symbol ()
(interactive)
(call-interactively (if (use-rtags) 'rtags-find-symbol 'gtags-find-symbol)))
(defun tags-find-references ()
(interactive)
(call-interactively (if (use-rtags) 'rtags-find-references 'gtags-find-rtag)))
(defun tags-find-file ()
(interactive)
(call-interactively (if (use-rtags t) 'rtags-find-file 'gtags-find-file)))
(defun tags-imenu ()
(interactive)
(call-interactively (if (use-rtags t) 'rtags-imenu 'idomenu)))
(define-key c-mode-base-map (kbd "M-.") (function tags-find-symbol-at-point))
(define-key c-mode-base-map (kbd "M-,") (function tags-find-references-at-point))
(define-key c-mode-base-map (kbd "M-;") (function tags-find-file))
(define-key c-mode-base-map (kbd "C-.") (function tags-find-symbol))
(define-key c-mode-base-map (kbd "C-,") (function tags-find-references))
(define-key c-mode-base-map (kbd "C-<") (function rtags-find-virtuals-at-point))
(define-key c-mode-base-map (kbd "M-i") (function tags-imenu))
(define-key global-map (kbd "M-.") (function tags-find-symbol-at-point))
(define-key global-map (kbd "M-,") (function tags-find-references-at-point))
(define-key global-map (kbd "M-;") (function tags-find-file))
(define-key global-map (kbd "C-.") (function tags-find-symbol))
(define-key global-map (kbd "C-,") (function tags-find-references))
(define-key global-map (kbd "C-<") (function rtags-find-virtuals-at-point))
(define-key global-map (kbd "M-i") (function tags-imenu))
Code Completion in Emacs:
To enable code completion in Emacs with company mode do the following:
- Enable rtags-diagnostics. The easiest way is to:
(setq rtags-autostart-diagnostics t)
but you can also explicitly start it with
M-x rtags-diagnostics <RET>
- Enable completions in RTags:
(setq rtags-completions-enabled t)
- Enable company-mode
(require 'company)
(global-company-mode)
- Add company-rtags to company-backends:
(push 'company-rtags company-backends)
This minimal init.el configuration should be enough to get completion to work.
(require 'package)
(package-initialize)
(require 'rtags)
(require 'company)
(setq rtags-autostart-diagnostics t)
(rtags-diagnostics)
(setq rtags-completions-enabled t)
(push 'company-rtags company-backends)
(global-company-mode)
(define-key c-mode-base-map (kbd "<C-tab>") (function company-complete))
To enable completion in Emacs with auto-complete-mode do the following: …TODO…
RTags Flycheck integration
To turn on RTags Flycheck support you need to load the flycheck-rtags
package.
(require 'flycheck-rtags)
Optional
You may explicitly select the RTags Flycheck checker for some major modes for better experience.
At the moment there is no customize option available to choose between
rtags-diagnostics
overlays or Flycheck overlays, nor is it planned right
now.
We recommend setting flycheck-highlighting-mode
locally to nil
as the
RTags overlays are more accurate.
Further, Flycheck will trigger automatically, based on events, the syntax
checker for the current buffer, this is however, pretty useless in conjunction
with RTags. We trigger it manually because we find it gives you a better
experience.
To turn off the automatic Flycheck syntax checking, set the variable
flycheck-check-syntax-automatically
locally to nil
.
(defun my-flycheck-rtags-setup ()
(flycheck-select-checker 'rtags)
(setq-local flycheck-highlighting-mode nil) ;; RTags creates more accurate overlays.
(setq-local flycheck-check-syntax-automatically nil))
(add-hook 'c-mode-hook #'my-flycheck-rtags-setup)
(add-hook 'c++-mode-hook #'my-flycheck-rtags-setup)
(add-hook 'objc-mode-hook #'my-flycheck-rtags-setup)
Helm integration
You can use Helm to view the result, to do so, set
rtags-display-result-backend
to helm
. You don’t need to load helm-rtags
,
we do it. If you have installed RTags through MELPA you need to install
helm-rtags
.
(setq rtags-display-result-backend 'helm)
Ivy integration
You can use Ivy to view the result, to do so, set
rtags-display-result-backend
to ivy
. You don’t need to load ivy-rtags
,
we do it. If you have installed RTags through MELPA you need to install
ivy-rtags
.
(setq rtags-display-result-backend 'ivy)
Videos
Here are some videos demonstrating how to use RTags with Emacs though some of these may be outdated:
Set up symlinks and run the daemon
“IMenu” / virtuals / filenames
Debugging RTags
If you find that rp
is crashing (leading to output like this: “job crashed
191 9698036154370 0x331e7e30”). You should be able to do the following:
rdm --suspend-rp-on-crash
When rp
crashes the rp
process will stay alive, enabling you to debug it
with something like this:
gdb -p `pidof rp`
Support for other editors
There are several other projects integrating RTags with other editors.
Sublime Text: https://github.com/rampage644/sublime-rtags
Vim: https://github.com/lyuts/vim-rtags https://github.com/shaneharper/vim-rtags https://github.com/mattn/vim-rtags
Note to those maintainers. If you need RTags to behave differently or add features to make these other integration’s easier (like produce output in other formats etc), just drop us a note.
Disclaimer
RTags is still under development and is not the most stable piece of software you’ll ever find. We’re constantly working to improve on it.