Undocumented make feature?

[Soren A]

Hello!

I came across a WWW site that claimed this:

GLIB_CFLAGS=`pkg-config --cflags glib-2.0`
GLIB_LIBS=`pkg-config --libs glib-2.0`
FOOBAR_OBJS =
#...
.PHONY: foobar.exe
foobar.exe : $(FOOBAR_OBJS)
           @echo $@ $(FOOBAR_OBJS) $(GLIB_LIBS)

and I couldn't believe it, so I tried it. It works.

Is this an undocumented feature, Paul? The only references to backquotes
I find in the 'make' manual state that "the <shell> function works like
backquotes do in a shell" -- but doesn't say that _backquotes
themselves_ work in a Makefile. 

I believe that I detect liberal addition of sugar the 'make' stew by 
somebody along the way ... ;-) 

What's the status of this? Deprecated? Going to disappear someday? Maybe
better forget I ever read it? 

    Regards,
      Soren A