Make:Diagnostic fail if no eval
To help diagnose make problems, we report an error if the make
program used does not provide the $(eval ) make functionality.
This will detect early versions of GNU make and other make programs.
Change-Id: I0ebb0f63694cf0b04eaeb7ea1e9e172fb9770ce0
diff --git a/make_helpers/build_macros.mk b/make_helpers/build_macros.mk
index 274f365..42e11b3 100644
--- a/make_helpers/build_macros.mk
+++ b/make_helpers/build_macros.mk
@@ -28,6 +28,12 @@
# POSSIBILITY OF SUCH DAMAGE.
#
+# Report an error if the eval make function is not available.
+$(eval eval_available := T)
+ifneq (${eval_available},T)
+ $(error This makefile only works with a Make program that supports $$(eval))
+endif
+
# Some utility macros for manipulating awkward (whitespace) characters.
blank :=
space :=${blank} ${blank}
