Re: LONG: Limitations of Make (Portable Shell Programming chapter of Autoconf)

[Nicolas Joly]

On Sun, Mar 24, 2002 at 07:16:08PM +0100, Alexandre Duret-Lutz wrote:
> 
[...]
> `VPATH'
>      There is no `VPATH' support specified in POSIX.  Many Makes have a
>      form of `VPATH' support, but its implementation is not coherent
>      amongst Makes.
> 
>      Maybe the best suggestion to do to people who needs the `VPATH'
>      feature is to chose a Make implementation an stick to it.  Since
>      the resulting `Makefile's are not portable anyway, better chose a
>      portable Make (hint, hint).
> 
>      Here are a couple of known issues with some `VPATH'
>      implementations.
[...]
>     OSF/Tru64 make creates prerequisite directories magically
>           When a prerequisite is a sub-directory of `VPATH', Tru64 Make
>           will create it in the current directory.
> 
>                % cat Makefile
>                VPATH = ..
>                all : foo/bar
>                % make -p foo/bar build
                   ^^^^
mkdir

>                % cd build
>                % make
>                mkdir foo
>                mkdir foo/bar
> 
>           This can yield unexpected results if a rule uses a manual
>           `VPATH' search as presented before.
> 
>                VPATH = ..
>                all : foo/bar
>                        command `test -d foo/bar || echo ../`foo/bar
> 
>           The above `command' will be run on the empty `foo/bar'
>           directory created in the current directory.

-- 
Nicolas Joly

Biological Software and Databanks.
Pasteur Institute, Paris.