Uploaded image for project: 'Qt'
  1. Qt
  2. QTBUG-52739

must not use pkg-config to find EGL on Raspberry Pi



    • Type: Bug
    • Status: Closed
    • Priority: P2: Important
    • Resolution: Out of scope
    • Affects Version/s: 5.5.1, 5.6.0
    • Fix Version/s: None
    • Component/s: Build System



      it's been some days I'm working on it.
      I'm trying to compile meta-qt5 for Yocto with the RaspberryPi.

      To summarize:
      RaspberryPi can link with: -lEGL -lGLESv2 and can't with -lGLESv2 -lEGL

      I was looking on RaspberryPi side first and found out that they properly feed pkg-config.
      Then I went into meta-qt5 and found out that... other BSP layers adds some weird patches to have EGL working.
      I did not want any patch and kept digging.

      When you use pkg-config, you feed "libs" variable and in the ./config.tests/qpa/egl/egl.pro file, you are looking for QMAKE_LIBS_EGL.

      So... you set libs and take the default of QMAKE_LIBS_EGL.
      With the RaspberryPi, libs = -lEGL -lGLESv2 ... and the default is QMAKE_LIBS_EGL = -lEGL.

      => -lEGL -lGLESv2 -lEGL => -lGLESv2 -lEGL => can't link

      I think that you want to keep the pkg-config functionnality AND the QMAKE_LIBS_EGL variable... Which is set to the default value!!!

      What should be done is:
      If pkg-config then don't take QMAKE_LIBS_EGL into account unless QMAKE_LIBS_EGL is also properly set.

      I guess that was what the guy who wrote this configure part thought. But the variable QMAKE_LIBS_EGL computed in the configure does not pass to the egl.pro file.

      I'll paste extracts. And hope we will correct it together.


          Issue Links

          For Gerrit Dashboard: QTBUG-52739
          # Subject Branch Project Status CR V



              • Assignee:
                buddenha Oswald Buddenhagen
                jgueytat JulienGueytat
              • Votes:
                0 Vote for this issue
                6 Start watching this issue


                • Created:

                  Gerrit Reviews

                  There are no open Gerrit changes