Re: [Mingw-msys] RE: Differences between mingw-make and msys' make

[Paul D. Smith]

%% Earnie Boyd <address@hidden> writes:

  >> True, but just having the variable VPATH set in your makefile doesn't
  >> _hurt_ anything.  It's just another unused variable.  This is why we
  >> recommend using VPATH wherever possible: using the vpath syntax is GNU
  >> make specific and a syntax error in other versions of make.
  eb>                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  eb> Yes, so, if you're concerned about being portable with multiple
  eb> vendors of make then dependency with VPATH operation makes it
  eb> non-portable.

Note I said that "vpath" (lowercase) creates a syntax error, because the
format is:

  vpath <pattern> <pathlist>

which is a syntax error in standard make.  VPATH (uppercase) is just a
variable setting:

  VPATH = <pathlist>

so if you use it in a makefile and the make you use doesn't handle
VPATH, it's just treated as a normal variable with no special
characteristics.

Obviously you're correct in that if your makefile _requires_ VPATH
behavior or it won't work, then this is not going to help.

But the GNU makefiles (at least those generated by automake) are very
carefully constructed so that they will work without VPATH support, if
you build in the source directory.  So, using VPATH here does _not_ make
those makefiles non-portable, it just means you don't have as many
options as you would if you did use GNU make.

If you want to build outside the source directory, _then_ you need a
make which understands VPATH and gives it mostly the same semantics as
GNU make does.


Probably everyone reading this understands all this perfectly well and
I'm just beating a dead horse so... I'll be quite now :).

-- 
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 Paul D. Smith <address@hidden>          Find some GNU make tips at:
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 "Please remain calm...I may be mad, but I am a professional." --Mad Scientist