OK to build Qt5 with -no-mitshm on Linux?

pyl0420

Hi:

XCB or X11 is totally out of my expertise, so forgive me if I say anything stupid.

For some reason, we build qt4 with -no-mitshm for many years, can I still use this option with Qt5? The reason I am asking is because:

http://qt-project.org/doc/qt-5/linux-requirements.html, it is a bit confusing that xcb-shm is required. So what happens if I say no for mit-shm?
Apparently even I turned off mit-shm , QXcbShmImage is still used somewhere, and it leads to some sporadic crashes in QXcbShmImage::destroy() when it is trying to free some data. Not sure whether it has something to do with " -no-mitshm"

Any hint would be really helpful!!
Thanks!
-Ollie

ambershark

It should be fine to compile with -no-mitshm if you want.

However, mit-shm allows for transferring of images via shared memory instead of over a socket for X windows. Keeping it enable will result in some pretty big performance increases in your software.

I've never turned off that feature so I'm not sure why you are getting crashes in destroy. Try a stack trace when it crashes and see what is happening and why.