Re: Issue with foreach statement

[Paul Smith]

On Wed, 2016-07-27 at 11:26 -0600, Brian Vandenberg wrote:
> Fortunately this is rather easy to reproduce without foreach:
> 
> > 
> >     $ cat /tmp/makefile
> > 
> >     define TEST_MACRO =
> >     $(eval a=b)
> >     $(eval a=b)
> >     endef
> > 
> >     $(call TEST_MACRO)
> > 
> >     $ make -f /tmp/makefile
> >     /tmp/makefile:8: *** missing separator.  Stop.
> The issue is that the evaluation of TEST_MACRO produced a non-empty
> string consisting of whitespace.

Ah.  It's even simpler to reproduce:

  define TEST_MACRO


  endef

  $(call TEST_MACRO)

(note that's two blank lines in the define)

It's not whitespace per se, it's the newline.  Just using spaces alone
won't cause a problem.  This probably SHOULD be considered a bug in
make; it should be able to ignore blank lines in this context just like
whitespace.

> You can resolve this problem by wrapping the foreach in a $(strip):
> 
> > 
> >     $(strip $(foreach ...))

Yes, and also you can just write:

  TEST_MACRO = $(eval a=a) $(eval b=b)

(you don't need define/endef for this) which also ensures there are no
newlines in the content of TEST_MACRO.