[strongSwan] Cannot compile strong-swan from git

[Martin Willi]

Hi Ben,

> First, maybe autogen could detect this missing gperf right at the
> beginning and tell the user?

./autogen.sh is just a wrapper for autogen -i these days, so it won't
help users calling that directly.

Doing such a check in ./configure is no option, as gperf is not
required for an ordinary build from tarball. The gperf (and other)
output is part of the distribution tarball, so that users don't need
non-standard tools.

> confread.o: In function `load_conn':
> /home/greearb/git/strongswan/src/starter/confread.c:568: undefined
> reference to `in_word_set'

Try "make maintainer-clean", and start from scratch with autogen and
./configure.

The problem here is that the gperf rule generates an empty file if
gperf is missing, and then "make" thinks the file is up to date once
gperf got installed. I've tried to address this issue with [1].

Regards
Martin

[1] https://git.strongswan.org/?p=strongswan.git;a=commitdiff;h=bca7571b0fa17b3b0c448187166833ad3664250c