Re: [PATCH iproute2 v4 0/5] configure: add support for libdir and prefix option

On Fri, Oct 08, 2021 at 03:50:25PM +0200, Phil Sutter wrote:

[...]

quoted

This avoid the endless loop and allows configure to terminate correctly,
but results in an error anyway:

$ ./configure --include_dir
./configure: line 544: shift: shift count out of range

Ah, I didn't see it with bash. I don't think it's a problem though:
Input is invalid, the loop is avoided and (depending on your patches)
there will be another error message complaining about invalid $INCLUDE
value.

Yes, this error can be disregarded. Still I would try to avoid a
meaningless error message, if possible.

[...]

Which sounds like you'll start accepting things like

| ./configure --include_dir foo bar

We already accept things like this in the current configure, and I would
try to not modify current behaviour as much as possible.

[...]

quoted

quoted

Can't you just:

| [ -n "$PREFIX" ] && echo "PREFIX=\"$PREFIX\"" >>config.mk
| [ -n "$LIBDIR" ] && echo "LIBDIR=\"$LIBDIR\"" >>config.mk

and leave the default ("?=") cases in Makefile in place?

Either way, calling 'eval' seems needless. I would avoid it at all
costs, "eval is evil". ;)

Unfortunately this is needed because some packaging systems uses
${prefix} as an argument to --libdir, expecting this to be replaced with
the value of --prefix. See Luca's review to v1 for an example [1].

I can always avoid the eval trying to parse "${prefix}" and replacing it
with the PREFIX value, but in this case "eval" seems a bit more
practical to me... WDYT?

Do autotools support that? If not, I wouldn't bother.

I don't know about autotools, but Debian packaging system makes use of
this, and we cannot break their workflow.

Regards,
Andrea