Minor build system improvements - force default shell.

[pub/lufa.git] / LUFA / Build / lufa.sources.in

diff --git a/LUFA/Build/lufa.sources.in b/LUFA/Build/lufa.sources.in
index d5316ba..a475ece 100644 (file)
--- a/LUFA/Build/lufa.sources.in
+++ b/LUFA/Build/lufa.sources.in
@@ -52,9 +52,11 @@ LUFA_BUILD_PROVIDED_MACROS +=
 #
 # -----------------------------------------------------------------------------
 
-ERROR_IF_UNSET   = $(if $(filter undefined, $(origin $(strip $(1)))), $(error Makefile $(strip $(1)) value not set))
-ERROR_IF_EMPTY   = $(if $(strip $($(strip $(1)))), , $(error Makefile $(strip $(1)) option cannot be blank))
-ERROR_IF_NONBOOL = $(if $(filter Y N, $($(strip $(1)))), , $(error Makefile $(strip $(1)) option must be Y or N))
+SHELL = /bin/sh
+
+ERROR_IF_UNSET   ?= $(if $(filter undefined, $(origin $(strip $(1)))), $(error Makefile $(strip $(1)) value not set))
+ERROR_IF_EMPTY   ?= $(if $(strip $($(strip $(1)))), , $(error Makefile $(strip $(1)) option cannot be blank))
+ERROR_IF_NONBOOL ?= $(if $(filter Y N, $($(strip $(1)))), , $(error Makefile $(strip $(1)) option must be Y or N))
 
 # Sanity check user supplied values
 $(foreach MANDATORY_VAR, $(LUFA_BUILD_MANDATORY_VARS), $(call ERROR_IF_UNSET, $(MANDATORY_VAR)))