Debugging WebKitGTK+

You need a compilation with symbols (take it easy as it'll take some time/hours):

$ Tools/Scripts/build-webkit --gtk --debug

On 32-bits arch it is quite unlikely this build will succeed. If you need a build with debug symbols but still without ASSERTs enabled you can try these options:

$ Tools/Scripts/build-webkit --gtk --disable-fast-malloc --enable-debug-symbols=full --disable-optimizations

In other to run GtkLauncher under gdb you should use a jhbuild shell and run gdb normally or use the jhbuild-wrapper as follows:

$ Tools/jhbuild/jhbuild-wrapper --gtk run gdb --args WebKitBuild/Debug/Programs/GtkLauncher --debug

Debugging multimedia stuff

You can use the environment variable GST_DEBUG:

$ export GST_DEBUG="webkit*:5"

To debug a multimedia test inside DRT (Dump Render Tree):

$ Tools/Scripts/run-webkit-tests --gtk --additional-env-var=GST_DEBUG=webkit*:5 --additional-env-var=GST_DEBUG_NO_COLOR=1 http/tests/media/video-play-stall.html

Debugging tests

• In order to run tests inside the @jhbuild@ shell, these two environment variables must be set:

  $ export TEST_RUNNER_TEST_PLUGIN_PATH=$WEBKIT_HOME/WebKitBuild/Release/Libraries/.libs/
  $ export TEST_RUNNER_INJECTED_BUNDLE_FILENAME=$WEBKIT_HOME/WebKitBuild/Release/Libraries/libTestRunnerInjectedBundle.la
  

Debugging issues

• Some times when running the WebKitTestRunner (WK2) you can see linking errors like the following one:

  (lt-WebKitWebProcess:3392): WARNING **: Error loading the injected bundle (/home/javi/devel/WebKit/webkit.git/WebKitBuild/Debug/Libraries/libTestRunnerInjectedBundle.la): /home/javi/devel/WebKit/webkit.git/WebKitBuild/Debug/Libraries/.libs/libTestRunnerInjectedBundle.so: undefined symbol: _ZTVN7leveldb10ComparatorE
  

  • One possible cause of such errors are missing symbols in the Source/autotools/symbols.filter. These symbols are automatically exposed in the by the libWebCoreInternals library via tags. Such library expose some symbols for testing purposes, just like the WTR application does.
  • The symbols.filter should be updated by a fresh checkout, but if that's not the case, it's possible to workaround the issue by manually adding the missing symbols to the file.

Related

• Tracking memory errors in WebKitGTK+