Gentoo ~ # emerge -1ua texlive

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

Calculating dependencies... done!
[ebuild     U  ] dev-texlive/texlive-latex-2019 [2017]
[ebuild     U  ] dev-texlive/texlive-plaingeneric-2019 [2017]
[ebuild     U  ] dev-texlive/texlive-fontsrecommended-2019 [2017]
[ebuild     U  ] dev-texlive/texlive-fontutils-2019 [2017]
[ebuild     U  ] dev-texlive/texlive-fontsextra-2019 [2017]
[ebuild     U  ] dev-texlive/texlive-bibtexextra-2019 [2017]
[ebuild     U  ] dev-texlive/texlive-langcjk-2019 [2017]
[ebuild     U  ] dev-texlive/texlive-latexrecommended-2019-r2 [2017]
[ebuild     U  ] dev-texlive/texlive-mathscience-2019 [2017]
[ebuild     U  ] dev-texlive/texlive-latexextra-2019-r2 [2017]
[blocks b      ] =dev-texlive/texlive-latexextra-2017* ("=dev-texlive/texlive-latexextra-2017*" is blocking dev-texlive/texlive-mathscience-2019, dev-texlive/texlive-latexrecommended-2019-r2)
[ebuild     U  ] dev-texlive/texlive-formatsextra-2019 [2017]
[ebuild     U  ] app-text/texlive-2019-r1 [2017]
[blocks B      ] dev-tex/xcolor ("dev-tex/xcolor" is blocking dev-texlive/texlive-latexrecommended-2019-r2)
[blocks B      ] =dev-texlive/texlive-pstricks-2017* ("=dev-texlive/texlive-pstricks-2017*" is blocking dev-texlive/texlive-latexextra-2019-r2)

 * Error: The above package list contains packages which cannot be
 * installed at the same time on the same system.

  (dev-tex/xcolor-2.12-r1:0/0::gentoo, installed) pulled in by
    dev-tex/xcolor required by (dev-tex/latex-beamer-3.36:0/0::gentoo, installed)
    dev-tex/xcolor required by (dev-tex/pgf-3.1.4-r1:0/0::gentoo, installed)

  (dev-texlive/texlive-latexrecommended-2019-r2:0/0::gentoo, ebuild scheduled for merge) pulled in by
    dev-texlive/texlive-latexrecommended required by (dev-texlive/texlive-luatex-2019:0/0::gentoo, installed)
    >=dev-texlive/texlive-latexrecommended-2019 required by (app-text/texlive-2019-r1:0/0::gentoo, ebuild scheduled for merge)
    dev-texlive/texlive-latexrecommended required by (dev-tex/glossaries-4.41:0/0::gentoo, installed)
    dev-texlive/texlive-latexrecommended required by (virtual/latex-base-1.0:0/0::gentoo, installed)
    dev-texlive/texlive-latexrecommended required by (dev-tex/dot2texi-3.0:0/0::gentoo, installed)
    dev-texlive/texlive-latexrecommended required by (dev-tex/pgf-3.1.4-r1:0/0::gentoo, installed)
    >=dev-texlive/texlive-latexrecommended-2019 required by (dev-texlive/texlive-latexextra-2019-r2:0/0::gentoo, ebuild scheduled for merge)

  (dev-texlive/texlive-pstricks-2017:0/0::gentoo, installed) pulled in by
    dev-texlive/texlive-pstricks required by (dev-texlive/texlive-mathscience-2019:0/0::gentoo, ebuild scheduled for merge)

  (dev-texlive/texlive-latexextra-2019-r2:0/0::gentoo, ebuild scheduled for merge) pulled in by
    >=dev-texlive/texlive-latexextra-2012 required by (dev-tex/glossaries-4.41:0/0::gentoo, installed)
    >=dev-texlive/texlive-latexextra-2010 required by (dev-texlive/texlive-xetex-2017:0/0::gentoo, installed)
    >=dev-texlive/texlive-latexextra-2008 required by (dev-tex/europecv-20060424-r2:0/0::gentoo, installed)
    >=dev-texlive/texlive-latexextra-2019 required by (app-text/texlive-2019-r1:0/0::gentoo, ebuild scheduled for merge)
    dev-texlive/texlive-latexextra required by (dev-tex/dot2texi-3.0:0/0::gentoo, installed)
    dev-texlive/texlive-latexextra required by (dev-tex/biblatex-3.7-r1:0/0::gentoo, installed)


For more information about Blocked Packages, please refer to the following
section of the Gentoo Linux x86 Handbook (architecture is irrelevant):

https://wiki.gentoo.org/wiki/Handbook:X86/Working/Portage#Blocked_packages