I know nothing about autotools, so I should probably stop talking, but not quite yet.
You say GNUMAKEFLAGS+=-r is "invalid syntax" but I don't know quite how to read that. It's not invalid in the sense of causing an error, it's just that it would be invisible to any non-GNU make program so presumably that's what you mean. But the thing is, I don't believe other make programs are reactive to MAKEFLAGS being set within the makefile. At least, it's been a long time since I read POSIX but I don't think it's required. My assumption may be wrong but if not, setting MAKEFLAGS would be a NOP in non-GNU makes anyway. Except that it would take effect in recursive invocations but that complicates things further. Anyway, I really should stop talking since I know zero about automake. David On Mon, Jul 17, 2023 at 11:22 AM Bruno Haible <br...@clisp.org> wrote: > David Boyce wrote: > > Everything else aside, there's a profound difference between MAKEFLAGS=-r > > and MAKEFLAGS+=-r. The latter is far less destabilizing. > > At least the '-n' option does not get lost by MAKEFLAGS=-r. That is, > setting MAKEFLAGS=-r and running 'make -n' does not cause the actions > to be actually executed. > > > And yes, GNUMAKEFLAGS is definitely better for this use. > > But MAKEFLAGS+=-r or GNUMAKEFLAGS+=-r is not something one can use in a > Makefile.am, since this is invalid syntax for a POSIX make program. > Thus, for those who want to get rid of implicit rules because Automake > provides the rules already, it's either MAKEFLAGS=-r or nothing at all. > > Bruno > > > >
