Enhance makefile to autodetect if AVOIDCOMBINE is needed.
diff --git a/Makefile b/Makefile
index eebc4d1..186ef51 100644
--- a/Makefile
+++ b/Makefile
@@ -54,10 +54,14 @@
################ Build rules
+ifndef AVOIDCOMBINE
+AVOIDCOMBINE=$(shell CC=$(CC) tools/test-combine.sh)
+endif
+
# Do a whole file compile - two methods are supported. The first
# involves including all the content textually via #include
# directives. The second method uses gcc's "-combine" option.
-ifdef AVOIDCOMBINE
+ifeq "$(AVOIDCOMBINE)" "1"
define whole-compile
@echo " Compiling whole program $3"
$(Q)printf '$(foreach i,$2,#include "../$i"\n)' > $3.tmp.c