BUILD: prepare the makefile to skip format lines in SUBVERS and VERDATE
We're going to put format lines in these files for use by git archive,
so let's ensure that the current default format still works. For this
we'll use two lines and only take the first one without a format tag.
diff --git a/Makefile b/Makefile
index e1a7424..4a51985 100644
--- a/Makefile
+++ b/Makefile
@@ -356,10 +356,10 @@
VERSION := $(shell cat VERSION 2>/dev/null || touch VERSION)
endif
ifeq ($(SUBVERS),)
-SUBVERS := $(shell cat SUBVERS 2>/dev/null || touch SUBVERS)
+SUBVERS := $(shell (grep -v '^\$$' SUBVERS 2>/dev/null || touch SUBVERS) | head -n 1)
endif
ifeq ($(VERDATE),)
-VERDATE := $(shell cat VERDATE 2>/dev/null || touch VERDATE)
+VERDATE := $(shell (grep -v '^\$$' VERDATE 2>/dev/null || touch VERDATE) | head -n 1)
endif
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