I want to give vkdt a try, but when I try to compile it on debian bullseye, I get:
qvk/qvk.c:62:25: error: use of undeclared identifier 'VK_API_VERSION_1_3'
.apiVersion = VK_API_VERSION_1_3,
here is the full error message
Appreciate your help 
I have libvulkan-dev installed.
heya, thanks for trying to compile.
any particular reason to stay with bullseye and not go to bookworm? at some point i updated the vk requirements in the code to 1.3 (bullseye has 1.2) because it has some features that are interesting for future development… but can look into a feature downgrade here.
okay pushed a downgrade. please pull and try again.
Hey Jo, thanks for your quick reply. I’m currently in production and want to delay upgrading, also because I’m considering switching to alma linux soon.
awesome!
Unfortunately I got this now:
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [tools/flat.mk:26: ../bin/vkdt-mkclut] Fehler 1
make[2]: *** Es wird auf noch nicht beendete Prozesse gewartet....
/usr/bin/ld: /tmp/eval-12d98d.o: in function `fs_basedir':
/home/j/repos/vkdt/src/./core/fs.h:100: undefined reference to `dlopen'
/usr/bin/ld: /home/j/repos/vkdt/src/./core/fs.h:103: undefined reference to `dlinfo'
/usr/bin/ld: /home/j/repos/vkdt/src/./core/fs.h:105: undefined reference to `dlclose'
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [tools/flat.mk:32: ../bin/vkdt-eval-profile] Fehler 1
/usr/bin/ld: /tmp/mkssf-8692ab.o: in function `fs_basedir':
/home/j/repos/vkdt/src/./core/fs.h:100: undefined reference to `dlopen'
/usr/bin/ld: /home/j/repos/vkdt/src/./core/fs.h:103: undefined reference to `dlinfo'
/usr/bin/ld: /home/j/repos/vkdt/src/./core/fs.h:105: undefined reference to `dlclose'
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [tools/flat.mk:23: ../bin/vkdt-mkssf] Fehler 1
make[2]: Verzeichnis „/home/j/repos/vkdt/src“ wird verlassen
make[1]: *** [Makefile:82: src] Fehler 2
make[1]: Verzeichnis „/home/j/repos/vkdt“ wird verlassen
make: *** [Makefile:10: debug] Fehler 2
interesting. again please.
now it compiles, but crashes at startup:
[gui] glfwGetVersionString() : 3.3.2 X11 GLX EGL OSMesa clock_gettime evdev shared
[gui] monitor [0] HDMI-0 at 0 0
[gui] vk extension required by GLFW:
[gui] VK_KHR_surface
[gui] VK_KHR_xcb_surface
[ERR] init vulkan failed
[ERR] failed to init gui/swapchain
xrandr
Screen 0: minimum 8 x 8, current 2560 x 1440, maximum 32767 x 32767
HDMI-0 connected primary 2560x1440+0+0 (normal left inverted right x axis y axis) 640mm x 360mm
1920x1080 60.00 + 119.88 59.94 50.00 29.97 25.00 23.98
2560x1600 59.97
2560x1440 59.95*
1920x1200 59.88
1680x1050 59.95
1600x1200 60.00
1600x900 60.00
1440x900 59.89
1366x768 59.79
1280x1024 60.02
1280x800 59.81
1280x720 59.94 50.00
1024x768 60.00
800x600 60.32
720x576 50.00
720x480 59.94
640x480 59.94
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
DP-3 disconnected (normal left inverted right x axis y axis)
DP-4 disconnected (normal left inverted right x axis y axis)
DP-5 disconnected (normal left inverted right x axis y axis)
…could you run ./vkdt -d all to show some more diagnostic output? possible that vkdt picks the gpu that does not have a screen attached to it (you can only operate the cli on this one in this case).
Does not provide much more info.
$ ./vkdt -d all
[gui] glfwGetVersionString() : 3.3.2 X11 GLX EGL OSMesa clock_gettime evdev shared
[gui] monitor [0] HDMI-0 at 0 0
[gui] vk extension required by GLFW:
[gui] VK_KHR_surface
[gui] VK_KHR_xcb_surface
[qvk] error VK_ERROR_LAYER_NOT_PRESENT executing vkCreateInstance(&inst_create_info, NULL, &qvk.instance)!
[ERR] init vulkan failed
[ERR] failed to init gui/swapchain
did you build with debug info, i.e. make debug ? in this case you need to install the validation layers (i.e. vulkan-validationlayers on debian).
awesome! Works now
Thank you soo much for your time. 
Looking forward to work with your awesome software.
