make build-gnu.sh reentrant

Author: sylvestre

util/build-gnu.sh

@@ -89,15 +89,15 @@ cd -
 
 export CARGOFLAGS # tell to make
  "${MAKE}" UTILS=install
-ln -vf "${UU_BUILD_DIR}/install" "${UU_BUILD_DIR}/ginstall" # The GNU tests use renamed install to ginstall
+[ -e "${UU_BUILD_DIR}/ginstall" ] || ln -vf "${UU_BUILD_DIR}/install" "${UU_BUILD_DIR}/ginstall" # The GNU tests use renamed install to ginstall
 if [ "${SELINUX_ENABLED}" = 1 ];then
     # Build few utils for SELinux for faster build. MULTICALL=y fails...
     "${MAKE}" UTILS="cat chcon chmod cp cut dd echo env groups id ln ls mkdir mkfifo mknod mktemp mv printf rm rmdir runcon seq stat test touch tr true uname wc whoami"
 else
     # Use MULTICALL=y for faster build
     "${MAKE}" MULTICALL=y SKIP_UTILS="install more"
     for binary in $("${UU_BUILD_DIR}"/coreutils --list)
-        do ln -vf "${UU_BUILD_DIR}/coreutils" "${UU_BUILD_DIR}/${binary}"
+        do [ -e "${UU_BUILD_DIR}/${binary}" ] || ln -vf "${UU_BUILD_DIR}/coreutils" "${UU_BUILD_DIR}/${binary}"
     done
 fi