m4_ifndef([PKG_PROG_PKG_CONFIG],
[m4_fatal([Could not locate the pkg-config autoconf
macros. These are usually located in /usr/share/aclocal/pkg.m4.
m4_ifndef([PKG_PROG_PKG_CONFIG],
[m4_fatal([Could not locate the pkg-config autoconf
macros. These are usually located in /usr/share/aclocal/pkg.m4.