message: build: if cross-compiling for an apple host, locate some additional tools
  This should be safe to do for native builds too, but for now it's
  specific to cross-builds to avoid possible regressions.
diff: @@ -223,6 +223,7 @@ case $host in
  TARGET_OS=darwin
  LEVELDB_TARGET_FLAGS="TARGET_OS=Darwin"
  if test x$cross_compiling != xyes; then
  + BUILD_OS=darwin
  AC_CHECK_PROG([PORT],port, port)
  if test x$PORT = xport; then
  dnl add default macports paths
  @@ -239,6 +240,17 @@ case $host in
  CPPFLAGS="$CPPFLAGS -I$bdb_prefix/include"
  LIBS="$LIBS -L/$bdb_prefix/lib"
  fi
  + else
  + case $build_os in
  + *darwin*)
  + BUILD_OS=darwin
  + ;;
  + *)
  + AC_PATH_TOOL([INSTALLNAMETOOL], [install_name_tool], install_name_tool)
  + AC_PATH_TOOL([OTOOL], [otool], otool)
  + AC_PATH_PROGS([GENISOIMAGE], [genisoimage mkisofs],genisoimage)
  + ;;
  + esac
  fi
  if test x$use_qt = xyes; then
  @@ -693,6 +705,7 @@ if test x$use_tests = xyes; then
  fi
  AM_CONDITIONAL([TARGET_DARWIN], [test x$TARGET_OS = xdarwin])
  +AM_CONDITIONAL([BUILD_DARWIN], [test x$BUILD_OS = xdarwin])
  AM_CONDITIONAL([TARGET_WINDOWS], [test x$TARGET_OS = xwindows])
  AM_CONDITIONAL([USE_QRCODE], [test x$use_qr = xyes])
  AM_CONDITIONAL([USE_LCOV],[test x$use_lcov == xyes])
  