Re: [PATCH] use libcrypto routines in gnulib

[Karl Berry]

    Perhaps I'm reading too much into the standards, but that's how
    --with-jpeg etc. behave in GNU Emacs 'configure'.

FWIW, I think you are right, and --with should fail if the specified
package is not installed, per the standards text.  Alternatively, it
could configure "as if" the with-package will be installed, even if it's
not now, but as far as I have seen that is usually not possible.  (It
also seems pretty undesirable to me.)

The wording for --enable is not as clear-cut, but there I would say that
if the user explicitly asked to enable foo, and foo is not available,
they would prefer to abort over continuing anyway.

If we think different wording/behavior for the standards are desirable, 
we can certainly propose a change to rms.  I doubt he is hard-and-fast
on this question.

karl


File: standards.info,  Node: Configuration

[...]

`--enable-FEATURE[=PARAMETER]'
     Configure the package to build and install an optional user-level
     facility called FEATURE.  This allows users to choose which
     optional features to include.  Giving an optional PARAMETER of
     `no' should omit FEATURE, if it is built by default.

     No `--enable' option should *ever* cause one feature to replace
     another.  No `--enable' option should ever substitute one useful
     behavior for another useful behavior.  The only proper use for
     `--enable' is for questions of whether to build part of the program
     or exclude it.

`--with-PACKAGE'
     The package PACKAGE will be installed, so configure this package
     to work with PACKAGE.

     Possible values of PACKAGE include `gnu-as' (or `gas'), `gnu-ld',
     `gnu-libc', `gdb', `x', and `x-toolkit'.

     Do not use a `--with' option to specify the file name to use to
     find certain files.  That is outside the scope of what `--with'
     options are for.