It seems that dev-lang/lua misses a patch in the files directory:
* lua-5.1.5.tar.gz BLAKE2B SHA512 size ;-) ... [ ok ]
>>> Unpacking source...
>>> Unpacking lua-5.1.5.tar.gz to /var/tmp/portage/dev-lang/lua-5.1.5-r5/work
>>> Source unpacked in /var/tmp/portage/dev-lang/lua-5.1.5-r5/work
>>> Preparing source in /var/tmp/portage/dev-lang/lua-5.1.5-r5/work/lua-5.1.5 ...
* Applying lua-5.1.5-gentoo-build.patch ... [ ok ]
* Cannot find $EPATCH_SOURCE! Value for $EPATCH_SOURCE is:
* ( lua-5.1.5-disable-readline.patch )
* ERROR: dev-lang/lua-5.1.5-r5::gentoo failed (prepare phase):
* Cannot find $EPATCH_SOURCE!
* Call stack:
* ebuild.sh, line 125: Called src_prepare
* environment, line 3111: Called epatch '/var/tmp/portage/dev-lang/lua-5.1.5-r5/files/lua-5.1.5-disable-readline.patch'
* environment, line 818: Called die
* The specific snippet of code:
* die "Cannot find \$EPATCH_SOURCE!";
* If you need support, post the output of `emerge --info '=dev-lang/lua-5.1.5-r5::gentoo'`,
* the complete build log and the output of `emerge -pqv '=dev-lang/lua-5.1.5-r5::gentoo'`.
* The complete build log is located at '/var/tmp/portage/dev-lang/lua-5.1.5-r5/temp/build.log'.
* The ebuild environment file is located at '/var/tmp/portage/dev-lang/lua-5.1.5-r5/temp/environment'.
* Working directory: '/var/tmp/portage/dev-lang/lua-5.1.5-r5/work/lua-5.1.5'
* S: '/var/tmp/portage/dev-lang/lua-5.1.5-r5/work/lua-5.1.5
I think the ebuild uses the wrong file for patching.
r5 came with 719f9a18c8709bf355d7ea80c09cd4e87f0a11fe which also brought us lua-5.1.5-readline.patch which is actually unused.
So i guess instead of calling epatch lua-5.1.5-disable-readline.patch it would be correct to call epatch lua-5.1.5-readline.patch ?