docker build error: use changes are necessary to proceed

[mweibel]

Hi,

I'm not well versed in gentoo and emerge, so I'm not quite sure what to do about this error:

The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by dev-python/cryptography-2.6.1::gentoo
# required by dev-python/urllib3-1.24.2::gentoo
# required by dev-python/requests-2.21.0-r1::gentoo
# required by media-gfx/blender-2.79b-r1::gentoo
# required by media-gfx/blender (argument)
>=virtual/python-enum34-2 python_targets_python3_5

Use --autounmask-write to write changes to config files (honoring
CONFIG_PROTECT). Carefully examine the list of proposed changes,
paying special attention to mask or keyword changes that may expose
experimental or unstable packages.
The command '/bin/sh -c emerge media-gfx/blender' returned a non-zero code: 1

I tried adding those use changes in data/package.use/blender but then I got another error:

make[1]: *** [Makefile:2091: ks_tables.h] Error 134
make[1]: Leaving directory '/var/tmp/portage/x11-libs/libX11-1.6.8/work/libX11-1.6.8-abi_x86_64.amd64/src'
make: *** [Makefile:521: all-recursive] Error 1
 * ERROR: x11-libs/libX11-1.6.8::gentoo failed (compile phase):
 *   emake failed
 *
 * If you need support, post the output of `emerge --info '=x11-libs/libX11-1.6.8::gentoo'`,
 * the complete build log and the output of `emerge -pqv '=x11-libs/libX11-1.6.8::gentoo'`.
 * The complete build log is located at '/var/tmp/portage/x11-libs/libX11-1.6.8/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/x11-libs/libX11-1.6.8/temp/environment'.
 * Working directory: '/var/tmp/portage/x11-libs/libX11-1.6.8/work/libX11-1.6.8-abi_x86_64.amd64'
 * S: '/var/tmp/portage/x11-libs/libX11-1.6.8/work/libX11-1.6.8'

>>> Failed to emerge x11-libs/libX11-1.6.8, Log file:

>>>  '/var/tmp/portage/x11-libs/libX11-1.6.8/temp/build.log'
 * Messages for package dev-python/mako-1.0.6:
 *   dev-python/beaker for Caching support
 * Messages for package x11-libs/libX11-1.6.8:
 * ERROR: x11-libs/libX11-1.6.8::gentoo failed (compile phase):
 *   emake failed
 *
 * If you need support, post the output of `emerge --info '=x11-libs/libX11-1.6.8::gentoo'`,
 * the complete build log and the output of `emerge -pqv '=x11-libs/libX11-1.6.8::gentoo'`.
 * The complete build log is located at '/var/tmp/portage/x11-libs/libX11-1.6.8/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/x11-libs/libX11-1.6.8/temp/environment'.
 * Working directory: '/var/tmp/portage/x11-libs/libX11-1.6.8/work/libX11-1.6.8-abi_x86_64.amd64'
 * S: '/var/tmp/portage/x11-libs/libX11-1.6.8/work/libX11-1.6.8'





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 * Processed 80 info files.

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The command '/bin/sh -c emerge media-gfx/blender' returned a non-zero code: 1

Unsure if the changes I did were correct or not, anyway it doesn't seem to work.
Do you have an idea how to fix or further debug this?