GNUMakefile: Adjust cp invocation to what POSIX requires

"cp -a" is nonportable, as POSIX does not specify -a:
  https://pubs.opengroup.org/onlinepubs/9699919799/utilities/cp.html
Use -R -p instead.

Signed-off-by: Greg Troxel <gdt@lexort.com>
Reviewed-by: Rob Browning <rlb@defaultvalue.org>
Tested-by: Rob Browning <rlb@defaultvalue.org>

diff --git a/GNUmakefile b/GNUmakefile
index 812ea38851c79eb344d14b86c525b35d4db67437..767b0ee0f66a7e1ed714e33af1200686b51b3d42 100644 (file)
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -176,7 +176,7 @@ dev/python-proposed: dev/python.c src/bup/compat.c src/bup/io.c
 clean_paths += dev/python
 dev/python: dev/python-proposed
        dev/validate-python $@-proposed
-       cp -a $@-proposed $@
+       cp -R -p $@-proposed $@
 
 clean_paths += dev/bup-exec
 generated_dependencies += dev/bup-exec.d