Re: Can't comple qemu-system-aarch64 with egl-headless display

[Peter Maydell]

On Sun, 5 Sept 2021 at 16:01, Mike Ladouceur <mike.ladouceur@live.com> wrote:
>
> # This runs fine
> ./configure --enable-kvm --enable-system --enable-spice --enable-opengl 
> --enable-virglrenderer --enable-libusb --target-list=aarch64-softmmu
>
> # Make runs. with no errors
>
> # No egl-headless here
> $ qemu-system-aarch64 -display ?
> Available display backend types:
> none
> gtk
> sdl
> curses
> spice-app
>
> # I guess this would be expected if the egl-headless isn't listed above.
> $ qemu-system-aarch64 -display egl-headless
> qemu-system-aarch64: -display egl-headless: Invalid parameter 'egl-headless'

Hmm, so it built OK but didn't compile in the EGL support.
Which QEMU version are you using?

Looking at the configure/meson logic, I think that the problem here
is that egl-headless depends on two things: opengl and gbm. configure
provides an --enable-opengl to force configure to fail if it doesn't
find the opengl libraries, but there is no equivalent --enable-gbm
to force a failure, so if libgbm isn't present then the build system
always just falls back to "don't build the features that depend on it".

On Ubuntu I think what you want is in the 'libgbm-dev' package; try
installing that and then rerunning configure and make.

thanks
-- PMM