GHC new build system megapatch

1 files changed, 25 insertions, 0 deletions

diff --git a/rules/hi-rule.mk b/rules/hi-rule.mk
new file mode 100644
index 0000000000..07b65ed8e1
--- /dev/null
+++ b/rules/hi-rule.mk
@@ -0,0 +1,25 @@
+
+# Here's an interesting rule!
+# The .hi file depends on the .o file,
+# so if the .hi file is dated earlier than the .o file (commonly the case,
+# when interfaces are stable) this rule just makes sure that the .o file,
+# is up to date.  Then it does nothing to generate the .hi file from the
+# .o file, because the act of making sure the .o file is up to date also
+# updates the .hi file (if necessary).
+
+define hi-rule # $1 = way
+%.$$($1_hisuf) : %.$$($1_osuf)
+	@if [ ! -f $$@ ] ; then \
+	    echo Panic! $$< exists, but $$@ does not.; \
+	    exit 1; \
+	else exit 0 ; \
+	fi
+
+%.$$($1_way_)hi-boot : %.$$($1_way_)o-boot
+	@if [ ! -f $$@ ] ; then \
+	    echo Panic! $$< exists, but $$@ does not.; \
+	    exit 1; \
+	else exit 0 ; \
+	fi
+endef
+