egl/dri2: glFlush is not optional, treat it as such

The documentation is clear - one must glFlush the old context on
eglMakeCurrent. Thus keeping it optional is not something we should be
doing. Furthermore if we cannot get the entry point we're likely having
a broken setup/stack.

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

diff --git a/src/egl/drivers/dri2/egl_dri2.c b/src/egl/drivers/dri2/egl_dri2.c
index cd0a2e9b6253ce9a30784ad9378ee3d852ce07d9..e41ce004734635c11b1af6081cd8206f2ab88b22 100644 (file)
--- a/src/egl/drivers/dri2/egl_dri2.c
+++ b/src/egl/drivers/dri2/egl_dri2.c
@@ -1262,7 +1262,7 @@ dri2_make_current(_EGLDriver *drv, _EGLDisplay *disp, _EGLSurface *dsurf,
    }
 
    /* flush before context switch */
-   if (old_ctx && dri2_drv->glFlush)
+   if (old_ctx)
       dri2_drv->glFlush();
 
    ddraw = (dsurf) ? dri2_dpy->vtbl->get_dri_drawable(dsurf) : NULL;
@@ -2666,8 +2666,7 @@ dri2_client_wait_sync(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSync *sync,
       if (dri2_ctx && dri2_sync->base.SyncStatus == EGL_UNSIGNALED_KHR &&
           (flags & EGL_SYNC_FLUSH_COMMANDS_BIT_KHR)) {
          /* flush context if EGL_SYNC_FLUSH_COMMANDS_BIT_KHR is set */
-         if (dri2_drv->glFlush)
-            dri2_drv->glFlush();
+         dri2_drv->glFlush();
       }
 
       /* if timeout is EGL_FOREVER_KHR, it should wait without any timeout.*/
@@ -2832,6 +2831,12 @@ dri2_load(_EGLDriver *drv)
    dri2_drv->glFlush = (void (*)(void))
       dri2_drv->get_proc_address("glFlush");
 
+   /* if glFlush is not available things are horribly broken */
+   if (!dri2_drv->glFlush) {
+      _eglLog(_EGL_WARNING, "DRI2: failed to find glFlush entry point");
+      return EGL_FALSE;
+   }
+
    dri2_drv->handle = handle;
 
    return EGL_TRUE;