I had nearly given up trying to build from trunk on Fedora. Ran across this thread that helped.
https://bbs.archlinux.org/viewtopic.php?pid=1258673
Walkthrough:
$ sudo [or su -c] apt-get [or yum] install libtool autoconf automake git
(More development packages e.g. libusbx-devel are needed to actually build openocd.
Sorry - don't have a list.)
$ git clone git://git.code.sf.net/p/openocd/code openocd-code
$ cd openocd-code
$ libtoolize
libtoolize: putting auxiliary files in `.'.
libtoolize: linking file `./ltmain.sh'
libtoolize: You should add the contents of the following files to `aclocal.m4':
libtoolize: `/usr/share/aclocal/libtool.m4'
libtoolize: `/usr/share/aclocal/ltoptions.m4'
libtoolize: `/usr/share/aclocal/ltversion.m4'
libtoolize: `/usr/share/aclocal/ltsugar.m4'
libtoolize: `/usr/share/aclocal/lt~obsolete.m4'
libtoolize: Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
libtoolize: rerunning libtoolize, to keep the correct libtool macros in-tree.
libtoolize: Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
libtoolize: `AC_PROG_RANLIB' is rendered obsolete by `LT_INIT'
(modify configure.ac and Makefile.am as suggested)
$ libtoolize --force
libtoolize: putting auxiliary files in `.'.
libtoolize: linking file `./ltmain.sh'
libtoolize: putting macros in AC_CONFIG_MACRO_DIR, `m4'.
libtoolize: linking file `m4/libtool.m4'
libtoolize: linking file `m4/ltoptions.m4'
libtoolize: linking file `m4/ltsugar.m4'
libtoolize: linking file `m4/ltversion.m4'
libtoolize: linking file `m4/lt~obsolete.m4'
libtoolize: `AC_PROG_RANLIB' is rendered obsolete by `LT_INIT'
$ aclocal
$ autoheader
$ automake --force-missing --add-missing
configure.ac:22: installing './compile'
configure.ac:31: installing './config.guess'
configure.ac:31: installing './config.sub'
configure.ac:10: installing './install-sh'
configure.ac:10: installing './missing'
Makefile.am: installing './INSTALL'
doc/Makefile.am:1: installing 'doc/mdate-sh'
doc/Makefile.am:1: installing 'doc/texinfo.tex'
src/Makefile.am: installing './depcomp'
$ autoconf
At this point I had a working .configure script.
One hiccup I failed to document:
I think it was the configure script that gave an error due to missing jimtcl files.
It listed the specific git commands required to install.
Once I followed the instructions I was able to ./configure; make; make install; as if I had downloaded a regular release.