--- old/make/Init.gmk	2016-02-19 16:39:39.693941933 +0100
+++ new/make/Init.gmk	2016-02-19 16:39:39.605941929 +0100
@@ -154,6 +154,9 @@
           # Do nothing
         endif
 
+    # Do not let make delete spec files even if aborted while doing a reconfigure
+    .PRECIOUS: $(SPECS)
+
     # Unless reconfigure is explicitely called, let all main targets depend on
     # the spec files to be up to date.
     ifeq ($(findstring reconfigure, $(INIT_TARGETS)), )