Comment # 5 on bug 92301 from Michel Dänzer

(In reply to MC Return from comment #4)
> How can I find out if my 32-bit Mesa binaries are up to date ?

It sounds like you only built 64-bit binaries of Mesa yourself, so you're
probably still using the 32-bit binaries from Ubuntu. What does

 apt-cache policy libgl1-mesa-dri:i386

say?