build: don't assume distdir/scan.c is writeable

diff --git a/src/Makefile.am b/src/Makefile.am
index 2db07efa03a3a68587533af3feb5242f2f06d98b..b5827ab993b1a3c18c0e5ee57370b6278d0672ee 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -92,8 +92,9 @@ stage1scan.c: scan.c
 endif
 
 dist-hook: scan.l flex$(EXEEXT)
+       chmod u+w $(distdir)/scan.c && \
        ./flex$(EXEEXT) -o scan.c $< && \
-       mv scan.c $(distdir)
+       cp scan.c $(distdir)
 
 # make needs to be told to make parse.h so that parallelized runs will
 # not fail.