Re: new module 'gperf'

[Bruno Haible]

Benoit Sigoure wrote:
> > gllib/Makefile.am:579: GPERF multiply defined in condition TRUE ...
> > gllib/Makefile.am:548: ... `GPERF' previously defined here
> ...
> Do you think it would be an improvement if automake did not complain  
> because it could be clever enough to detect that even though the  
> variable is defined multiple times, it's always defined with the same  
> value?

No, I don't think this would be an improvement. The "one definition rule"
is a basic principle of declarative languages. Automake has enough magic
feature where it provides default values for variables that are not
explicitly defined. Additional magic for merging conflicting definitions
of the same variable would make things even more complex.

Recall that still 99% of the Makefile.am files are written by hand, and
allowing two lines

  GPERF = gperf
  ...
  GPERF = gperf

is only an invitation to the developer to write

  GPERF = gperf
  ...
  GPERF = gperf -m 10

- and get an error message, which is not what he wanted.

Bruno