diff --git a/config/nspr/Makefile.in b/config/nspr/Makefile.in
index 905f4b15dab..b814cab064f 100644
--- a/config/nspr/Makefile.in
+++ b/config/nspr/Makefile.in
@@ -33,8 +33,11 @@ clean distclean export::
 	$(MAKE) -C $(DEPTH)/nsprpub $@ $(EXTRA_MAKE_FLAGS)
 
 target::
-	$(MAKE) -C $(DEPTH)/nsprpub libs $(EXTRA_MAKE_FLAGS)
-	$(MAKE) -C $(DEPTH)/nsprpub install prefix=$(ABS_DIST)/sdk exec_prefix=$(ABS_DIST)/sdk bindir=$(ABS_DIST)/sdk/dummy includedir=$(ABS_DIST)/include/nspr libdir=$(ABS_DIST)/sdk/lib datadir=$(ABS_DIST)/sdk/dummy DESTDIR= $(EXTRA_MAKE_FLAGS)
+# nspr's libs and install rule re-export headers, and that can race with other
+# compilations, so use a separate directory here. The headers are exported
+# during export anyways.
+	$(MAKE) -C $(DEPTH)/nsprpub libs $(EXTRA_MAKE_FLAGS) dist_includedir=$(ABS_DIST)/nspr-include
+	$(MAKE) -C $(DEPTH)/nsprpub install prefix=$(ABS_DIST)/sdk exec_prefix=$(ABS_DIST)/sdk bindir=$(ABS_DIST)/sdk/dummy includedir=$(ABS_DIST)/nspr-include libdir=$(ABS_DIST)/sdk/lib datadir=$(ABS_DIST)/sdk/dummy DESTDIR= $(EXTRA_MAKE_FLAGS)
 	$(INSTALL) $(DEPTH)/nsprpub/config/nspr-config $(DIST)/sdk/bin
 	$(RM) -rf $(DIST)/sdk/dummy
 ifneq (,$(filter WINNT,$(OS_ARCH))) # {