Re: [PATCH] Makefile: add and use the ".DELETE_ON_ERROR" flag

Ævar Arnfjörð Bjarmason [off-list ref] writes:

Even if you don't care about the end result or making git easier to hack
on for people who don't share your setup, I'd think that making those
rules consistent across the board makes things less complex, not more.

I think that it is where we disagree.  "Remove $@+ and $@, generate
into $@+ and then move it to $@" idiom has a legitimate reason to be
used, and I do not want to see it blindly used where there is no
reason to do so.  It misleads less experienced readers.

If we write a custom script that does not promise atomicity, it is a
quite natural pattern to use, and it is clear to readers what is
going on, especially when "generate into $@+" step is done via
redirection.  I despise "$(CC) -o $@+ && mv $@+ $@" because there
simply shouldn't be a need to do so---unlike our custom script that
sends its output to its standard output, $(CC) ought to know better.

But as you said elsewhere, the patch in question is *not* about
adding more use of "mv $@+ $@" in inappropriate contexts, so let's
stop discussing it now.  We take advantage of .DELETE_ON_ERROR that
allows us to use the upfront "rm -f $@ $@+" we do in the idiom,
which is a good thing.