Subject: Re: [PATCH iproute2 v5 7/7] configure: add the --libdir option

From: Andrea Claudi <[email-masked]>
Date: Thu, 14 Oct 2021 13:02:41 +0200

On Thu, Oct 14, 2021 at 12:10:53PM +0200, Phil Sutter wrote:
> Hi Andrea,
> 
> On Thu, Oct 14, 2021 at 10:50:55AM +0200, Andrea Claudi wrote:
> [...]
> > diff --git a/Makefile b/Makefile
> > index 5eddd504..f6214534 100644
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -1,6 +1,8 @@
> >  # SPDX-License-Identifier: GPL-2.0
> >  # Top level Makefile for iproute2
> >  
> > +-include config.mk
> > +
> 
> Assuming config.mk may be missing (as dash-prefix is used).
> 
> >  ifeq ("$(origin V)", "command line")
> >  VERBOSE = $(V)
> >  endif
> > @@ -13,7 +15,6 @@ MAKEFLAGS += --no-print-directory
> >  endif
> >  
> >  PREFIX?=/usr
> > -LIBDIR?=$(PREFIX)/lib
> 
> Dropping this leads to trouble if config.mk is missing or didn't define
> it. Can't you just leave it in place? Usually config.mk would override
> it anyway, no?

config.mk may miss at the first make call, but the "all" target calls
config.mk, which in turns re-generate it. Thus LIBDIR is defined when
the target all executes.

Also, LIBDIR must be defined in config.mk, as a default value for it is
provided in configure, and will be used if the user does not provide it
at command line.

I verified this deleting config.mk and printing DEFINES in Makefile to
verify it includes the correct path for LIBDIR.