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

Calculating dependencies ... done!
Dependency resolution took 1.11 s (backtrack: 0/20).

[ebuild  N     ] virtual/fortran-0-r1::gentoo  USE="openmp" 0 KiB
[ebuild  N     ] dev-cpp/range-v3-0.12.0-r1::gentoo  USE="-test" 570 KiB
[ebuild  N     ] dev-libs/rapidjson-1.1.0_p20250205::gentoo  USE="-doc -examples -test" 1091 KiB
[ebuild  N     ] sci-libs/coinor-utils-2.11.12:0/3::gentoo  USE="bzip2 zlib -blas -doc -glpk -lapack -static-libs -test" 1216 KiB
[ebuild  N     ] dev-libs/cereal-1.3.2-r4::gentoo  USE="-doc -test" 377 KiB
[ebuild  N     ] sci-libs/coinor-osi-0.108.11:0/1::gentoo  USE="-doc -examples -static-libs -test" 1014 KiB
[ebuild  N     ] sci-libs/coinor-clp-1.17.10:0/1::gentoo  USE="-doc -examples -glpk -metis -mpi -mumps -sparse -static-libs -test" 2132 KiB
[ebuild  N     ] sci-libs/coinor-vol-1.5.4:0/1::gentoo  USE="-doc -examples -static-libs -test" 961 KiB
[ebuild  N     ] sci-libs/coinor-cgl-0.60.9:0/1::gentoo  USE="-doc -examples -static-libs -test" 1262 KiB
[ebuild  N     ] sci-libs/coinor-cbc-2.10.12:0/3::gentoo  USE="-doc -examples -static-libs -test" 1648 KiB
[ebuild  N     ] sci-libs/lemon-1.3.1-r2::gentoo  USE="coin -doc -glpk -static-libs -test" 5023 KiB
[ebuild  N     ] sci-biology/seqan-3.1.0::gentoo  CPU_FLAGS_X86="sse4_2" 2594 KiB

Total: 12 packages (12 new), Size of downloads: 17883 KiB