Problem reported to me by a NetBSD user: m4/gnu-make.m4 […] has wrong assumptions:
11 # Set GNU_MAKE if we are using a recent-enough version of GNU make. 12 13 # Use --version AND trailing junk, because SGI Make doesn't fail on --version. 14 15 AC_DEFUN([gl_GNU_MAKE], 16 [ 17 AM_CONDITIONAL([GNU_MAKE], 18 [${MAKE-make} --version /cannot/make/this >/dev/null 2>&1]) 19 ]) (Of course on NetBSD make --version /cannot/make/this cleanly return a succesfull exit status!) ...and indeed in config.log we can see: [...] GNU_MAKE_FALSE='#' GNU_MAKE_TRUE='' [...] -- https://rrt.sc3d.org