SDL_mixer failed on x86_64 dockyard-devel (c64.arklinux.org)

SDL_mixer failed to build on x86_64 for dockyard-devel.
Last 250 lines of build log:

Installing SDL_mixer-1.2.8-1ark.src.rpm
Building target platforms: x86_64
Building for target x86_64
Executing(%prep): /bin/sh -e /var/tmp/rpm-tmp.16870
+ umask 022
+ cd /build-SDL_mixer-x86_64/BUILD
+ cd /build-SDL_mixer-x86_64/BUILD
+ rm -rf SDL_mixer-1.2.8
+ tar -xf /usr/src/ark/SOURCES/SDL_mixer-1.2.8.tar.lz
+ cd SDL_mixer-1.2.8
++ /usr/bin/id -u
+ '[' 0 = 0 ']'
+ /bin/chown -Rhf root .
++ /usr/bin/id -u
+ '[' 0 = 0 ']'
+ /bin/chgrp -Rhf root .
+ /bin/chmod -Rf a+rX,g-w,o-w .
+ echo 'Patch #0 (SDL_mixer-1.2.7-ark.patch):'
Patch #0 (SDL_mixer-1.2.7-ark.patch):
+ patch -p1 -b --suffix .ark~ -s
+ echo 'Patch #1 (SDL_mixer-1.2.5-uClibc.patch):'
Patch #1 (SDL_mixer-1.2.5-uClibc.patch):
+ patch -p1 -b --suffix .uClibc~ -s
+ echo 'Patch #2 (SDL_mixer-1.2.7-autoconf260.patch):'
Patch #2 (SDL_mixer-1.2.7-autoconf260.patch):
+ patch -p1 -b --suffix .ac260~ -s
+ exit 0
Executing(%build): /bin/sh -e /var/tmp/rpm-tmp.16870
+ umask 022
+ cd /build-SDL_mixer-x86_64/BUILD
+ cd SDL_mixer-1.2.8
+ libtoolize --force
You should add the contents of `/usr/share/aclocal/libtool.m4' to `aclocal.m4'.
Putting files in AC_CONFIG_AUX_DIR, `build-scripts'.
+ aclocal
/usr/share/aclocal/nspr.m4:8: warning: underquoted definition of AM_PATH_NSPR
/usr/share/aclocal/nspr.m4:8:   run info '(automake)Extending aclocal'
/usr/share/aclocal/nspr.m4:8:   or see http://sources.redhat.com/automake/automake.html#Extending-aclocal
configure.in:325: warning: macro `AM_PATH_SMPEG' not found in library
+ autoconf
configure.in:326: error: possibly undefined macro: AM_PATH_SMPEG
      If this token and others are legitimate, please use m4_pattern_allow.
      See the Autoconf documentation.
error: Bad exit status from /var/tmp/rpm-tmp.16870 (%build)


RPM build errors:
    Bad exit status from /var/tmp/rpm-tmp.16870 (%build)