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

Calculating dependencies ... done!
Dependency resolution took 1.09 s (backtrack: 0/20).

[ebuild  N     ] net-libs/mbedtls-2.28.10:0/7.14.1::gentoo  USE="threads -cmac -doc -havege -programs -static-libs -test -zlib" CPU_FLAGS_X86="sse2" 3408 KiB
[ebuild  N     ] dev-libs/libatomic_ops-7.10.0::gentoo  531 KiB
[ebuild  N     ] dev-libs/boehm-gc-8.2.12::gentoo  USE="large threads -cxx -static-libs" 1204 KiB
[ebuild  N     ] dev-libs/libpcre-8.45-r4:3::gentoo  USE="bzip2 cxx jit pcre16 readline (unicode) zlib -libedit -pcre32 -static-libs -valgrind" 1542 KiB
[ebuild  N     ] dev-lang/neko-2.4.1:0/2.4.1::gentoo  USE="sqlite ssl -apache -mysql" 507 KiB

Total: 5 packages (5 new), Size of downloads: 7190 KiB