MAKEFILE_LIST no longer correct

the version of make has what appears to be a broken for the MAKEFILE_LIST macro.

This is commonly used to get the currently loaded makefile.

However for some reason in this distribution the variable is not behaving as it should be.

From https://www.gnu.org/software/make/manual/html_node/Special-Variables.html

MAKEFILE_LIST

    Contains the name of each makefile that is parsed by make, in the order in which it was parsed. The name is appended just before make begins to parse the makefile. Thus, if the first thing a makefile does is examine the last word in this variable, it will be the name of the current makefile. Once the current makefile has used include, however, the last word will be the just-included makefile.

However in the attached program you can see a use that this is violated. The "ZZZfiles" definition has been set in wibble.mk which occurs before the include statement that includes another.mk however another.mk is in the variable as shown when the variable is printed.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: make 4.0-8.2
ProcVersionSignature: Ubuntu 4.2.0-16.19-generic 4.2.3
Uname: Linux 4.2.0-16-generic x86_64
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
CurrentDesktop: Unity
Date: Thu Jan 7 20:50:15 2016
Dependencies:
 gcc-5-base 5.2.1-22ubuntu2
 libc6 2.21-0ubuntu4
 libgcc1 1:5.2.1-22ubuntu2
InstallationDate: Installed on 2015-11-24 (44 days ago)
InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021)
SourcePackage: make-dfsg
UpgradeStatus: No upgrade log present (probably fresh install)