diff --git a/tools/Unix.mk b/tools/Unix.mk
index 2207e9f28bd..0597afc6e3a 100644
--- a/tools/Unix.mk
+++ b/tools/Unix.mk
@@ -740,7 +740,8 @@ savedefconfig: apps_preconfig
 # that the archiver is 'ar'
 
 export: $(NUTTXLIBS)
-	$(Q) MAKE="${MAKE}" $(MKEXPORT) $(MKEXPORT_ARGS) -l "$(EXPORTLIBS)"
+	$(Q) ZIG="${ZIG}" ZIGFLAGS="${ZIGFLAGS}" MAKE="${MAKE}" \
+		$(MKEXPORT) $(MKEXPORT_ARGS) -l "$(EXPORTLIBS)"
 
 # General housekeeping targets:  dependencies, cleaning, etc.
 #
diff --git a/tools/Zig.defs b/tools/Zig.defs
index 870d7372fb1..b1de13117e7 100644
--- a/tools/Zig.defs
+++ b/tools/Zig.defs
@@ -39,4 +39,6 @@ endif
 
 # Convert cortex-xxx/sifive-exx to cortex_xxx/sifive_exx
 
+ifneq ($(LLVM_CPUTYPE),)
 ZIGFLAGS += -mcpu $(subst -,_,$(LLVM_CPUTYPE))
+endif
diff --git a/tools/mkexport.sh b/tools/mkexport.sh
index 14d3e39e495..e78839089b6 100755
--- a/tools/mkexport.sh
+++ b/tools/mkexport.sh
@@ -243,6 +243,8 @@ echo "NM               = ${NM}" >>"${EXPORTDIR}/scripts/Make.defs"
 echo "STRIP            = ${STRIP}" >>"${EXPORTDIR}/scripts/Make.defs"
 echo "OBJCOPY          = ${OBJCOPY}" >>"${EXPORTDIR}/scripts/Make.defs"
 echo "OBJDUMP          = ${OBJDUMP}" >>"${EXPORTDIR}/scripts/Make.defs"
+echo "ZIG              = ${ZIG}" >>"${EXPORTDIR}/scripts/Make.defs"
+echo "ZIGFLAGS         = ${ZIGFLAGS}" >>"${EXPORTDIR}/scripts/Make.defs"
 echo "NXFLATLDFLAGS1   = ${NXFLATLDFLAGS1}" >>"${EXPORTDIR}/scripts/Make.defs"
 echo "NXFLATLDFLAGS2   = ${NXFLATLDFLAGS2}" >>"${EXPORTDIR}/scripts/Make.defs"
 echo "OBJEXT           = ${OBJEXT}" >>"${EXPORTDIR}/scripts/Make.defs"