-${B}rev.h: FORCE
- @if [ -f $@ ]; then prevrev=`cat $@`; else prevrev="00"; fi; \
- if [ "`which svn`" != "" ]; then \
- rev=`svn update|tail -n 1|sed 's/.*\ \(.*\)\./\1/g'|sed "s/'//g"`; \
- fi; \
- if [ "$$rev" = "" ]; then rev="0"; fi; \
- if [ "$$rev" != "$$prevrev" ]; then \
- echo "$$rev" > $@; \
- fi
-
+${C}revision.h: FORCE
+ @(git describe || echo) | sed -e 's/.*/#define REV "\0"/' > $@_
+ @diff -q $@_ $@ > /dev/null 2>&1 || cp $@_ $@
+ @rm $@_