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

Calculating dependencies ... done!
Dependency resolution took 1.53 s (backtrack: 0/20).

[ebuild     UD ] dev-libs/isl-0.26:0/23::gentoo [0.27:0/23::gentoo] USE="-static-libs" 1988 KiB

Total: 1 package (1 downgrade), Size of downloads: 1988 KiB