Re: new module 'iconv_open'

[Simon Josefsson]

Bruno Haible <address@hidden> writes:

> John Darrington wrote:
>> ./configure could show a warning if gperf is not found or is too old.
>
> What do you gain by knowing this at configure time, rather than at "make"
> time, a little later? To proceed with the build, you need to install gperf
> anyway.

I admit there is no strong technical reason to do this, but I consider
it good style.  Configure can print a warning message that gperf may
be needed if you are building from VC-sources, or if the user modify
some files.  Configure often check for dependencies, and prints
warnings/errors about them, so people expect that to happen (and will
look for such messages).  In the 'make' phase, people don't expect
build failures unless the configure phase somehow failed or warned
about something.  Alternatively, if the 'make' phase failed, some
people will look at the Configure output to see if they can find odd
warnings that may be related.

For example, in GnuTLS, I recently received a patch that added a
configure-time warning about missing non-required tools:

AC_PATH_PROG([GAA], [gaa])
if test "x$GAA" = "x"; then
   AC_MSG_WARN([[***
*** GAA was not found.  It is only needed if you wish to modify
*** the source code or command-line description files.  In this case,
*** you may want to get it from http://gaa.sourceforge.net/
***]])
fi

Before it would just fail during 'make' if gaa was not available.

/Simon