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

Calculating dependencies ... done!
Dependency resolution took 0.97 s (backtrack: 0/20).

[ebuild   R    ] dev-libs/spdlog-1.17.0:0/1.17::gentoo  USE="-test" 276 KiB

Total: 1 package (1 reinstall), Size of downloads: 276 KiB