Re: kern/54861: Possible wrong dependencies with MODULE and COMPAT_50

[Paul Goyette <paul%whooppee.com@localhost>]

The following reply was made to PR kern/54861; it has been noted by GNATS.

From: Paul Goyette <paul%whooppee.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/54861: Possible wrong dependencies with MODULE and COMPAT_50
Date: Wed, 15 Jan 2020 10:00:42 -0800 (PST)

 On Wed, 15 Jan 2020, Paul Goyette wrote:
 
 >> #      link  MODULAR/netbsd
 >> /s/src/obj.sun3/tooldir.NetBSD-9.0_RC1-i386/bin/m68k--netbsdelf-ld -Map 
 >> netbsd.map --cref -N -Ttext 0E004000 -e start -S -o netbsd 
 >> ${SYSTEM_OBJ:[@]:Nswapnetbsd.o} ${EXTRA_OBJ} vers.o swapnetbsd.o
 >> /s/src/sys/arch/sun3/compile/obj.sun3/MODULAR/lib/compat/libcompat.o: In 
 >> function `compat_14_rt_oifmsg':
 >> (.text+0x2c1e): undefined reference to `compat_50_route_info'
 >> /s/src/sys/arch/sun3/compile/obj.sun3/MODULAR/lib/compat/libcompat.o: In 
 >> function `compat_14_rt_oifmsg':
 >> (.text+0x2cf8): undefined reference to `compat_50_rt_msg1'
 >> /s/src/sys/arch/sun3/compile/obj.sun3/MODULAR/lib/compat/libcompat.o: In 
 >> function `compat_14_rt_oifmsg':
 >> (.text+0x2d0a): undefined reference to `compat_50_route_enqueue'
 >> 
 >> *** Failed target:  netbsd
 >
 > With a -current amdy4 build host, I get a slightly more informative
 > error message:
 >
 > #      link  MODULAR/netbsd
 > /build/netbsd-8/tools/x86_64/sun3/bin/m68k--netbsdelf-ld -Map netbsd.map 
 > --cref -N -Ttext 0E004000 -e start -X -o netbsd 
 > ${SYSTEM_OBJ:[@]:Nswapnetbsd.o} ${EXTRA_OBJ} vers.o swapnetbsd.o
 > /build/netbsd-8/obj/sun3/sys/arch/sun3/compile/MODULAR/lib/compat/libcompat.o: 
 > In function `compat_14_rt_oifmsg':
 > /build/netbsd-8/src/sys/compat/common/rtsock_14.c:99: undefined reference to 
 > `compat_50_route_info'
 > /build/netbsd-8/src/sys/compat/common/rtsock_14.c:125: undefined reference to 
 > `compat_50_rt_msg1'
 > /build/netbsd-8/src/sys/compat/common/rtsock_14.c:128: undefined reference to 
 > `compat_50_route_enqueue'
 > *** [netbsd] Error code 1
 >
 > It is totally unclear to me why ld(1) includes the rtsock_14.o member
 > from the libcompat.o library.  This object/member only defines two
 > symbols, compat_14_iflist and compat_14_rt_oifmsg, and neither of these
 > is referenced by any other object module.  A GENERIC (non-MODULAR)
 > kernel does not include rtsock_14.o member.
 
 OK, I unserstanad what's going on.  For MODULAR kernels, we use the
 libcompat.o aggregated object module rather that libcompat.a archive.
 This causes us to include all compat code, whether or not covered by
 the various COMPAT_xx options.  On top of that, it turns out that the
 rtsock_50.c code is built, but without having COMPAT_50 defined, so
 it ends up being a no-op with none of its routines defined.  The end
 result is a rtsock_14.o referencing routines that were ifdef'd out
 from rtsock_50.
 
 The following fix works.  I'll see if we can get it committed to the
 8.x and 8.1 branches.
 
 Index: rtsock_50.c
 ===================================================================
 RCS file: /cvsroot/src/sys/compat/common/rtsock_50.c,v
 retrieving revision 1.4.10.1
 diff -u -p -r1.4.10.1 rtsock_50.c
 --- rtsock_50.c	9 Jun 2018 14:38:18 -0000	1.4.10.1
 +++ rtsock_50.c	15 Jan 2020 17:59:56 -0000
 @@ -65,10 +65,11 @@ __KERNEL_RCSID(0, "$NetBSD: rtsock_50.c,
 
   #ifdef _KERNEL_OPT
   #include "opt_compat_netbsd.h"
 +#include "opt_modular.h"
   #endif
 
 -#if defined(COMPAT_14) && !defined(COMPAT_50)
 -#define	COMPAT_50	1	/* 1.4 needs 5.0 */
 +#if (defined(MODULAR) || defined(COMPAT_14)) && !defined(COMPAT_50)
 +#define	COMPAT_50	1	/* MODULAR and 1.4 need 5.0 */
   #endif
 
   #if defined(COMPAT_50)
 
 
 
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