bsd make and .IMPSRC - incomplete documentation?

[Aleksey Cheusov]

Hi. May be I missed something important but the following Makefile
doesn't work as it is documented.

man make says

.IMPSRC The name/path of the source from which the target
is to be transformed (the ``implied'' source);
also known as `<'.

IMPSRC is expanded to the empty string. What's wrong?


~> cat Makefile
file.ext : file.src
cp ${.IMPSRC} ${.TARGET}
~> touch file.src
~> make file.ext
cp file.ext
usage: cp [-R [-H | -L | -P]] [-f | -i] [-pv] src target
cp [-R [-H | -L | -P]] [-f | -i] [-pv] src1 ... srcN directory
*** Error code 1

Stop.
make: stopped in /home/cheusov
~>

[Masao Uebayashi]

.IMPSRC is expanded to the empty string. What's wrong?

As far as I understand by experience (!), ${.IMPSRC} works only when
suffix rule is applied. Bad make manual!

Masao

[David Laight]

Post by Masao Uebayashi

.IMPSRC is expanded to the empty string. What's wrong?

As far as I understand by experience (!), ${.IMPSRC} works only when
suffix rule is applied. Bad make manual!

I believe that is the historic behaviour for $<

David

[Aleksey Cheusov]

Post by David Laight

Post by Masao Uebayashi

.IMPSRC is expanded to the empty string. What's wrong?

As far as I understand by experience (!), ${.IMPSRC} works only when
suffix rule is applied. Bad make manual!

I believe that is the historic behaviour for $<

Ok. I'd like to see this better documented and sent PR about this.