using $eval to include other makefiles

[Hiran Morar]

Hello,

I've noticed multiple ways of including a Makefile within another Makefile.
For example, one could directly include the Makefile:

     # Filename top.mk
     ...
     include /path/to/file.mk

One could also use the $eval function to include the Makefile:

     # Filename: top.mk
     ...
     $(eval include /path/to/file.mk)

Both work fine. What's the difference? Is there an optimal or preferred
method?

Thanks!
Hiran