Would it not to be better to just do something like

override FLAGS += $(if $(release),--release )$(if $(stats),--stats )$(if $(progress),--progress )$(if $(threads),--threads $(threads) )$(if $(debug),-d )$(if $(static),--static )$(if $(LDFLAGS),--link-flags="$(LDFLAGS)" )

That way specifying make all FLAGS=--totally-existant-flag would just prepend --totally-existant-flag to the old FLAGS. And you wouldn't have to type the extra EXTRA_

Yeah thats what I meant, I should learn more makefile...

That way specifying make all FLAGS=--totally-existant-flag would just prepend --totally-existant-flag to the old FLAGS. And you wouldn't have to type the extra EXTRA_

That indeed an option, but it would not be backward compatible – now you can completely override FLAGS. If Crystal maintainers are okay with this change of behaviour, I’ll change it to the suggested variant.

I had the same concern at first but then there are actually no default values in FLAGS, all depend on another variable being set. So previously specifying FLAGS and for example release didn't work, you already had to do FLAGS=--release --whatever, which will continue to work just the same. Only if you would have specified release=1 FLAGS=--release there would be a slight change, but that was kinda invalid previously already.

With my suggested change, make all release=1 FLAGS=--no-debug would build with the flags --no-debug --release

@Jens0512 Is override really necessary? I think that FLAGS += … should work too; what difference does it make?

@jirutka Override is absolutely necessary

@jirutka See RX14s, and my comment for why.