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

Calculating dependencies ... done!
Dependency resolution took 0.98 s (backtrack: 0/20).

[ebuild   R    ] app-alternatives/yacc-1-r2::gentoo  USE="bison -byacc (-reference)" 0 KiB

Total: 1 package (1 reinstall), Size of downloads: 0 KiB