This issue was reported in the Buildroot mailing list, it happens with the latest releases (at least 2.16.5 and 2.16.6), and also with “trunk”. The error is: /home/peko/buildroot/output/build/webkitgtk-2.16.5/DerivedSources/WebCore/JSWebGLRenderingContextBase.cpp:3100:207: required from here /home/peko/buildroot/output/build/webkitgtk-2.16.5/Source/WTF/wtf/PassRefPtr.h:40:13: error: invalid use of incomplete type ‘class WebCore::HTMLVideoElement’ ptr->deref(); ^ In file included from /home/peko/buildroot/output/build/webkitgtk-2.16.5/Source/WebCore/html/canvas/WebGLRenderingContextBase.h:32:0, from /home/peko/buildroot/output/build/webkitgtk-2.16.5/DerivedSources/WebCore/JSWebGLRenderingContextBase.h:26, from /home/peko/buildroot/output/build/webkitgtk-2.16.5/DerivedSources/WebCore/JSWebGLRenderingContextBase.cpp:25: /home/peko/buildroot/output/build/webkitgtk-2.16.5/Source/WebCore/html/canvas/CanvasRenderingContext.h:40:7: note: forward declaration of ‘class WebCore::HTMLVideoElement’ class HTMLVideoElement; ^ Original report: http://lists.busybox.net/pipermail/buildroot/2017-July/198467.html
I looked a bit into this, and it's caused because MEDIA_STREAM is enabled anyway, and it tries to use the definition of HTMLVideoElement, which is guarded by ENABLE(VIDEO). This is due to a missing feature dependency in the CMake build files. We need to add: WEBKIT_OPTION_DEPEND(ENABLE_MEDIA_STREAM ENABLE_VIDEO) I'll be submitting a patch.
A test build with of “trunk” with “-DENABLE_MEDIA_STREAM=OFF” failed with: ../../Tools/TestWebKitAPI/Tests/WebKitGLib/WebExtensionTest.cpp:25:10: fatal error: gst/gst.h: No such file or directory #include <gst/gst.h> ^~~~~~~~~~~ If all of “-DENABLE_VIDEO=OFF”, “-DENABLE_WEB_AUDIO=OFF” and “-DENABLE_MEDIA_STREAM=OFF” is passed, then GStreamer is not needed, and no GStreamer flags are queried using “pkg-config”. Which results in the header not found. I think in this case we would want to guard the use of GStreamer in the tests as well, so I'll add that to the patch.
Created attachment 316646 [details] Patch
Comment on attachment 316646 [details] Patch Clearing flags on attachment: 316646 Committed r220007: <http://trac.webkit.org/changeset/220007>
All reviewed patches have been landed. Closing bug.