fix hostapd rebuild check, isolate the common src/ directory for hostapd variants as well to fix compile errors when both variants are selected (#2722)

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@9575 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 4 insertions, 6 deletions

diff --git a/rules.mk b/rules.mk
index 14ff5acdf..d36c99495 100644
--- a/rules.mk
+++ b/rules.mk
@@ -138,12 +138,10 @@ $(call shvar,$(1))=$$(call $(1))
 export $(call shvar,$(1))
 endef
 
-define confvar
-$(1):=$$(strip $$($(1)))_
-$(foreach v,$(2),
-  $(1):=$$(strip $$($(1)))$(if $($(v)),y,n)
-)
-endef
+empty:=
+space:= $(empty) $(empty)
+merge=$(subst $(space),,$(1))
+confvar=$(call merge,$(foreach v,$(1),$(if $($(v)),y,n)))
 
 # file extension
 ext=$(word $(words $(subst ., ,$(1))),$(subst ., ,$(1)))