These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.58 s (backtrack: 0/20).

[ebuild     U  ] dev-util/spirv-headers-1.4.363.0::gentoo [1.4.341.0::gentoo] 581 KiB
[ebuild  N     ] dev-libs/miniz-3.1.2:0/3.1.2::gentoo  284 KiB
[ebuild  N     ] dev-util/vulkan-headers-1.4.363.0::gentoo  USE="-test" 3337 KiB
[ebuild     U  ] dev-util/spirv-tools-1.4.363.0::gentoo [1.4.341.0::gentoo] USE="-test" 3474 KiB
[ebuild  N     ] dev-util/glslang-1.4.363.0:0/16.6::gentoo  4528 KiB
[ebuild  N     ] app-arch/lz4-1.10.0-r1:0/1.10.0-meson::gentoo  USE="-static-libs -test" 379 KiB
[ebuild  N     ] dev-util/shader-slang-2026.18.3:0/2026.18.3::gentoo  31179 KiB

Total: 7 packages (2 upgrades, 5 new), Size of downloads: 43758 KiB