====== Advanced Building and Debugging Information for Xfce components ======

While the basic build steps are explained here, this page provides some information about build specifics you probably will need on special occasions.

===== Debugging with gdb =====

For debian based systems, if you need to debug into dependencies, enable automatic download of debug symbols before calling GDB:

  export DEBUGINFOD_URLS="https://debuginfod.debian.net"
  
First make sure the application you want to debug is not running. After that, you can start it like this:

  gdb --args build/myapp/myapp-binary

E.g. for thunar:

  gdb --args build/thunar/thunar

Usually it is a good idea to automate the quitting and to bail out on the first warning:

  build/thunar/thunar -q; gdb --args build/thunar/thunar --g-fatal-warnings

On a freeze, get a backtrace of all threads via

  thread apply all bt

===== Build with documentation =====

  meson setup --reconfigure -Dgtk-doc=true build
  meson compile -C build

Documentation can be found below ''build/docs''

===== Use introspection / GtkInspector =====

''GtkInspector'' is a very nice tool to debug visual things during runtime. First you need to build the project with introspection support: 

Pre requirements:

  * install package libgirepository1.0-dev
  * gsettings set org.gtk.Settings.Debug enable-inspector-keybinding true

Building:

  meson setup --reconfigure -Dintrospection=true build
  meson compile -C build
  
Then you can start ''GtkInspector'' for the application by pressing {key>Ctrl+Shift+D} or {key>Ctrl+Shift+I} during runtime

[[https://developer.gnome.org/documentation/tools/inspector.html|Here some general gtk inspector information]]

===== Static analysis =====

==== Build with scan-build ====

''scan-build'' does some static code analysis for a project. It can be used like this:

  # using --reconfigure won't work ... you need to remove the build folder!
  rm -rf build
  
  # setup and build the project ... the concrete version of scan-build to use can differ
  CC=clang scan-build-19 --use-cc=clang meson setup build
  CC=clang scan-build-19 --use-cc=clang meson compile -C build

The reports are in HTML and can be viewed with a browser

==== Build with gcc static analyzer ====

  rm -rf build
  CPPFLAGS=-fanalyzer meson setup build
  meson compile -C build

==== Run cppcheck ====

You need to have xfce4-dev-tools >= 4.21.2 installed for this to work, so cppcheck founds the file ''$cppcheck_cfg_prefix/cppcheck/cfg/xfce.cfg''. If the default ''$cppcheck_cfg_prefix'' (''$libdir'') doesn't work for you (it works on ubuntu, so probably on any debian derived distro), you'll have to set it at configure time when building xfce4-dev-tools using the ''<nowiki>--with-cppcheck-cfg-prefix</nowiki>'' command line option.

See also the comment in the cppcheck job in [[https://gitlab.xfce.org/xfce/xfce4-dev-tools/-/blob/master/ci/build_project.yml|xfce4-dev-tools/ci/build_project.yml]] for more info on how to populate the file ''.cppcheck-false-positives'', and [[https://gitlab.xfce.org/xfce/xfce4-dev-tools/-/blob/master/ci/xfce.cfg|xfce4-dev-tools/ci/xfce.cfg]] as an example for the file ''.cppcheck.cfg'' if necessary.

  cppcheck -i build -j $(nproc) $([ -f .cppcheck.cfg ] && echo --library=.cppcheck.cfg) --library=gtk --library=xfce -I . \
    --suppressions-list=<(awk -F : '{print $1 ":" $2}' $([ -f .cppcheck-false-positives ] && echo .cppcheck-false-positives || echo /dev/null) | sort -u) \
    --enable=style --suppress=variableScope --suppress=constParameterPointer --suppress=constVariablePointer --suppress=constParameterCallback \
    --enable=information --check-level=exhaustive --force --suppress=unmatchedSuppression \
    --enable=warning,performance,portability --error-exitcode=1 $CPPCHECK_ARGS --quiet .