autoconf: Tru64 Directory Magic

1 
1 12.18.5 Tru64 `make' Creates Prerequisite Directories Magically
1 ---------------------------------------------------------------
1 
1 When a prerequisite is a subdirectory of `VPATH', Tru64 `make' creates
1 it in the current directory.
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1      $ mkdir -p foo/bar build
1      $ cd build
1      $ cat >Makefile <<END
1      VPATH = ..
1      all: foo/bar
1      END
1      $ make
1      mkdir foo
1      mkdir foo/bar
1 
1    This can yield unexpected results if a rule uses a manual `VPATH'
1 search as presented before.
1 
1      VPATH = ..
1      all : foo/bar
1              command `test -d foo/bar || echo ../`foo/bar
1 
1    The above `command' is run on the empty `foo/bar' directory that was
1 created in the current directory.
1