Re: gnu make question

[Paul D. Smith]

%% Trey Jackson <address@hidden> writes:

  tj> Is it possible to undefine a make variable?
  tj> Not just set it to an empty string, but actually undefine it?

Not that I can think of.

  tj> | MYVAR = value
  tj> | 
  tj> | ifdef MYVAR
  tj> |   # do something i want
  tj> | endif
  tj> | 
  tj> | 
  tj> | undef MYVAR
  tj> | 
  tj> | ifdef MYVAR
  tj> |   # skip this
  tj> | endif

Since ifdef only tests values to see if they're empty or not, you just
need:

  MYVAR =

in order to "undefine" it enough to placate ifdef.

-- 
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 Paul D. Smith <address@hidden>          Find some GNU make tips at:
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