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

Calculating dependencies  ... done!
[nomerge       ] dev-lang/rust-1.23.0-r1:stable/1.23::musl  USE="-debug -doc -extended -jemalloc -libressl -system-llvm" 
[ebuild  N    ~]  dev-util/cargo-0.24.0::musl  USE="bash-completion -debug -doc -libressl" 0 KiB
[ebuild  N    ~]   virtual/rust-1.23.0::gentoo  0 KiB
[ebuild  N    ~]    dev-lang/rust-1.23.0-r1:stable/1.23::musl  USE="-debug -doc -extended -jemalloc -libressl -system-llvm" 0 KiB

Total: 3 packages (3 new), Size of downloads: 0 KiB

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