This is required in order for autoconf's AC_PROG_INSTALL to use the sbase
install. Otherwise it will fall back to the slow and sucky install-sh script
from automake.
Given the following commands:
touch 1.txt; install -D 1.txt d/2.txt
find d
The result without this fix:
d
d/2.txt
d/2.txt/1.txt
The result with this patch applied:
d
d/2.txt