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

Calculating dependencies  .... . ..... done!
[ebuild     U  ] media-libs/libpng-1.6.37 [1.6.35-r1]
[ebuild  N     ] sys-devel/binutils-2.31.1-r4  USE="cxx gold nls plugins -default-gold -doc -multitarget -static-libs -test"

Would you like to merge these packages? [Yes/No]
>>> Verifying ebuild manifests

>>> Emerging (1 of 2) media-libs/libpng-1.6.37::gentoo
 * Fetching files in the background.
 * To view fetch progress, run in another terminal:
 * tail -f /var/log/emerge-fetch.log
 * libpng-1.6.37.tar.xz BLAKE2B SHA512 size ;-) ...                      [ ok ]
>>> Unpacking source...
>>> Unpacking libpng-1.6.37.tar.xz to /var/tmp/portage/media-libs/libpng-1.6.37/work
>>> Source unpacked in /var/tmp/portage/media-libs/libpng-1.6.37/work
>>> Preparing source in /var/tmp/portage/media-libs/libpng-1.6.37/work/libpng-1.6.37 ...
 * Running elibtoolize in: libpng-1.6.37/
 *   Applying portage/1.2.0 patch ...
 *   Applying sed/1.5.6 patch ...
 *   Applying as-needed/2.4.3 patch ...
 *   Applying ppc64le/2.4.4 patch ...
>>> Source prepared.
>>> Configuring source in /var/tmp/portage/media-libs/libpng-1.6.37/work/libpng-1.6.37 ...
 * abi_x86_64.amd64: running multilib-minimal_abi_src_configure
 * econf: updating libpng-1.6.37/config.guess with /usr/share/gnuconfig/config.guess
 * econf: updating libpng-1.6.37/config.sub with /usr/share/gnuconfig/config.sub
/var/tmp/portage/media-libs/libpng-1.6.37/work/libpng-1.6.37/configure --prefix=/usr --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --mandir=/usr/share/man --infodir=/usr/share/info --datadir=/usr/share --sysconfdir=/etc --localstatedir=/var/lib --disable-dependency-tracking --disable-silent-rules --docdir=/usr/share/doc/libpng-1.6.37 --htmldir=/usr/share/doc/libpng-1.6.37/html --libdir=/usr/lib64 --enable-intel-sse --disable-static --enable-arm-neon=no
checking for a BSD-compatible install... /usr/lib/portage/python3.6/ebuild-helpers/xattr/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking whether to enable maintainer-specific portions of Makefiles... no
checking for x86_64-pc-linux-gnu-gcc... x86_64-pc-linux-gnu-gcc
checking whether the C compiler works... no
configure: error: in `/var/tmp/portage/media-libs/libpng-1.6.37/work/libpng-1.6.37-abi_x86_64.amd64':
configure: error: C compiler cannot create executables
See `config.log' for more details

!!! Please attach the following file when seeking support:
!!! /var/tmp/portage/media-libs/libpng-1.6.37/work/libpng-1.6.37-abi_x86_64.amd64/config.log
 * ERROR: media-libs/libpng-1.6.37::gentoo failed (configure phase):
 *   econf failed
 *
 * Call stack:
 *               ebuild.sh, line  124:  Called src_configure
 *             environment, line 1401:  Called multilib-minimal_src_configure
 *             environment, line  903:  Called multilib_foreach_abi 'multilib-minimal_abi_src_configure'
 *             environment, line 1118:  Called multibuild_foreach_variant '_multilib_multibuild_wrapper' 'multilib-minimal_abi_src_configure'
 *             environment, line  833:  Called _multibuild_run '_multilib_multibuild_wrapper' 'multilib-minimal_abi_src_configure'
 *             environment, line  831:  Called _multilib_multibuild_wrapper 'multilib-minimal_abi_src_configure'
 *             environment, line  222:  Called multilib-minimal_abi_src_configure
 *             environment, line  897:  Called multilib_src_configure
 *             environment, line 1331:  Called econf '--enable-intel-sse' '--disable-static' '--enable-arm-neon=no'
 *        phase-helpers.sh, line  718:  Called __helpers_die 'econf failed'
 *   isolated-functions.sh, line  119:  Called die
 * The specific snippet of code:
 *   		die "$@"
 *
 * If you need support, post the output of `emerge --info '=media-libs/libpng-1.6.37::gentoo'`,
 * the complete build log and the output of `emerge -pqv '=media-libs/libpng-1.6.37::gentoo'`.
 * The complete build log is located at '/var/tmp/portage/media-libs/libpng-1.6.37/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/media-libs/libpng-1.6.37/temp/environment'.
 * Working directory: '/var/tmp/portage/media-libs/libpng-1.6.37/work/libpng-1.6.37-abi_x86_64.amd64'
 * S: '/var/tmp/portage/media-libs/libpng-1.6.37/work/libpng-1.6.37'

>>> Failed to emerge media-libs/libpng-1.6.37, Log file:

>>>  '/var/tmp/portage/media-libs/libpng-1.6.37/temp/build.log'
 * Messages for package media-libs/libpng-1.6.37:
 * ERROR: media-libs/libpng-1.6.37::gentoo failed (configure phase):
 *   econf failed
 *
 * Call stack:
 *               ebuild.sh, line  124:  Called src_configure
 *             environment, line 1401:  Called multilib-minimal_src_configure
 *             environment, line  903:  Called multilib_foreach_abi 'multilib-minimal_abi_src_configure'
 *             environment, line 1118:  Called multibuild_foreach_variant '_multilib_multibuild_wrapper' 'multilib-minimal_abi_src_configure'
 *             environment, line  833:  Called _multibuild_run '_multilib_multibuild_wrapper' 'multilib-minimal_abi_src_configure'
 *             environment, line  831:  Called _multilib_multibuild_wrapper 'multilib-minimal_abi_src_configure'
 *             environment, line  222:  Called multilib-minimal_abi_src_configure
 *             environment, line  897:  Called multilib_src_configure
 *             environment, line 1331:  Called econf '--enable-intel-sse' '--disable-static' '--enable-arm-neon=no'
 *        phase-helpers.sh, line  718:  Called __helpers_die 'econf failed'
 *   isolated-functions.sh, line  119:  Called die
 * The specific snippet of code:
 *   		die "$@"
 *
 * If you need support, post the output of `emerge --info '=media-libs/libpng-1.6.37::gentoo'`,
 * the complete build log and the output of `emerge -pqv '=media-libs/libpng-1.6.37::gentoo'`.
 * The complete build log is located at '/var/tmp/portage/media-libs/libpng-1.6.37/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/media-libs/libpng-1.6.37/temp/environment'.
 * Working directory: '/var/tmp/portage/media-libs/libpng-1.6.37/work/libpng-1.6.37-abi_x86_64.amd64'
 * S: '/var/tmp/portage/media-libs/libpng-1.6.37/work/libpng-1.6.37'