This used to be a deprecation WARNING but since 1.13 it's now an fatal ERROR. configure.ac:26: error: 'AM_CONFIG_HEADER': this macro is obsolete. You should use the 'AC_CONFIG_HEADERS' macro instead. /usr/share/aclocal-1.13/obsolete-err.m4:12: AM_CONFIG_HEADER is expanded from... configure.ac:26: the top level autom4te-2.69: /usr/bin/m4 failed with exit status: 1 aclocal-1.13: error: echo failed with exit status: 1 The solution is simple: sed -i -e 's:AM_CONFIG_HEADER:AC_CONFIG_HEADERS:' configure.ac.in As in, simply replacing AM_CONFIG_HEADER with AC_CONFIG_HEADERS (notice it's HEADERS, not HEADER) works and is backwards compatible.
Also, if you maintain more plugins, please do the same fix there too.
Fwiw i wasnt getting a warning/error with automake 1.14 / autoconf 2.65 on OpenBSD. Anyway, no regression, so fixed in ac70332