>>> Unpacking source...
>>> Unpacking db-4.3.29.tar.gz to /var/tmp/portage/sys-libs/db-4.3.29-r2/work
 * Applying db-4.3-libtool.patch ...
  [ ok ]
 * Applying db-4.3.27-fix-dep-link.patch ...
  [ ok ]
 * Applying db-4.3-jni-check-prefix-first.patch ...
  [ ok ]
 * Applying db-4.3-listen-to-java-options.patch ...
  [ ok ]
 * Using GNU config files from /usr/share/libtool
 *   Updating config.sub
  [ ok ]
 *   Updating config.guess
  [ ok ]
>>> Source unpacked.
>>> Compiling source in /var/tmp/portage/sys-libs/db-4.3.29-r2/work/db-4.3.29/build_unix ...
 * QA Notice: USE Flag 'userland_GNU' not in IUSE for sys-libs/db-4.3.29-r2
configure: WARNING: you should use --build, --host, --target
checking build system type... i686-gentoo-linux-uclibc
checking host system type... i686-gentoo-linux-uclibc
checking if building in the top-level or dist directories... no
checking if --disable-cryptography option specified... no
checking if --disable-hash option specified... no
checking if --disable-queue option specified... no
checking if --disable-replication option specified... no
checking if --disable-statistics option specified... no
checking if --disable-verify option specified... no
checking if --enable-compat185 option specified... yes
checking if --enable-cxx option specified... yes
checking if --enable-debug option specified... no
checking if --enable-debug_rop option specified... no
checking if --enable-debug_wop option specified... no
checking if --enable-diagnostic option specified... no
checking if --enable-dump185 option specified... no
checking if --enable-java option specified... no
checking if --enable-mingw option specified... no
checking if --enable-o_direct option specified... no
checking if --enable-posixmutexes option specified... no
checking if --enable-rpc option specified... yes
checking if --enable-smallbuild option specified... no
checking if --enable-tcl option specified... no
checking if --enable-test option specified... no
checking if --enable-uimutexes option specified... no
checking if --enable-umrw option specified... no
checking if --with-mutex=MUTEX option specified... no
checking if --with-mutexalign=ALIGNMENT option specified... no
checking if --with-tcl=DIR option specified... no
checking if --with-uniquename=NAME option specified... no
checking for i686-gentoo-linux-uclibc-ar... i686-gentoo-linux-uclibc-ar
checking for i686-gentoo-linux-uclibc-chmod... no
checking for chmod... chmod
checking for i686-gentoo-linux-uclibc-cp... no
checking for cp... cp
checking for i686-gentoo-linux-uclibc-ln... no
checking for ln... ln
checking for i686-gentoo-linux-uclibc-mkdir... no
checking for mkdir... mkdir
checking for i686-gentoo-linux-uclibc-ranlib... i686-gentoo-linux-uclibc-ranlib
checking for i686-gentoo-linux-uclibc-ranlib... /usr/bin/i686-gentoo-linux-uclibc-ranlib
checking for i686-gentoo-linux-uclibc-rm... no
checking for rm... rm
checking for i686-gentoo-linux-uclibc-rpcgen... no
checking for rpcgen... missing_rpcgen
configure: error: No rpcgen utility found.

!!! ERROR: sys-libs/db-4.3.29-r2 failed.
Call stack:
  ebuild.sh, line 1618:   Called dyn_compile
  ebuild.sh, line 975:   Called qa_call 'src_compile'
  environment, line 4649:   Called src_compile
  db-4.3.29-r2.ebuild, line 109:   Called die

!!! configure failed
!!! If you need support, post the topmost build error, and the call stack if relevant.
!!! A complete build log is located at '/var/tmp/portage/sys-libs/db-4.3.29-r2/temp/build.log'.

!!! When you file a bug report, please include the following information:
GENTOO_VM=  CLASSPATH="." JAVA_HOME="/etc/java-config-2/current-system-vm"
JAVACFLAGS="" COMPILER=""
and of course, the output of emerge --info