From ChangeLog
* VERSION: 20180222
Merge with NetBSD make, pick up
o parse.c: avoid calling sysconf for every call to loadfile
* VERSION: 20180218
Merge with NetBSD make, pick up
o var.c: Var_Set handle NULL value anytime.
* VERSION: 20180212
Merge with NetBSD make, pick up
o parse.c: do not treat .info as warning with -W
* VERSION: 20171207
Merge with NetBSD make, pick up
o var.c: Var_Append use Var_Set if var not previously set
so that VAR_CMD is handled correctly.
Add a suitable unit-test.
* VERSION: 20171126
* aclocal.m4: use AC_LINK_IFELSE for AC_C___ATTRIBUTE__
since AC_TRY_COMPILE puts input inside main()
which upsets modern compilers.
* VERSION: 20171118
Merge with NetBSD make, pick up
o var.c: do not append to variable set on command line
add unit-test to catch this.
