NET4501 w/options IPSEC breaks ipv6 at compile time?

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

I recently tried to build a custom 6.0_BETA2 kernel based on the NET4501
kernel configuration file, enabling "options IPSEC".  It failed compiling
with:

[...]
--- ip6_output.o ---
#   compile  NET4501_IPSEC/ip6_output.o
/d0/nbsd/netbsd-6/src/../tools/amd64/bin/i486--netbsdelf-gcc -mno-sse -mno-sse2 
-mno-sse3 -ffreestanding -fno-zero-initialized-in-bss -Os -fstack-protector 
-Wstack-protector --param ssp-buffer-size=1 -fno-strict-aliasing -std=gnu99 
-Werror -Wall -Wno-main -Wno-format-zero-length -Wpointer-arith 
-Wmissing-prototypes -Wstrict-prototypes -Wold-style-definition -Wswitch 
-Wshadow -Wcast-qual -Wwrite-strings -Wno-unreachable-code -Wno-pointer-sign 
-Wno-attributes -Wextra -Wno-unused-parameter -Wold-style-definition 
-Wno-sign-compare --sysroot=/d0/nbsd/netbsd-6/src/../DEST/i386 -Di386 -I. 
-I/d0/nbsd/netbsd-6/src/sys/../common/include -I/d0/nbsd/netbsd-6/src/sys/arch 
-I/d0/nbsd/netbsd-6/src/sys -nostdinc -DTIMER_FREQ=1189200 -DMAXUSERS=32 
-D_KERNEL -D_KERNEL_OPT -std=gnu99 
-I/d0/nbsd/netbsd-6/src/sys/lib/libkern/../../../common/lib/libc/quad 
-I/d0/nbsd/netbsd-6/src/sys/lib/libkern/../../../common/lib/libc/string 
-I/d0/nbsd/netbsd-6/src/sys/lib/libkern/../../../common/lib/libc/arch/i386/string
 -I/d0/nbsd/netbsd-6/src/sys/dist/ipf 
-I/d0/nbsd/netbsd-6/src/sys/external/isc/atheros_hal/dist 
-I/d0/nbsd/netbsd-6/src/sys/external/isc/atheros_hal/ic -c 
/d0/nbsd/netbsd-6/src/sys/netinet6/ip6_output.c
--- ip6_output.o ---
cc1: warnings being treated as errors
/d0/nbsd/netbsd-6/src/sys/netinet6/ip6_output.c: In function 'ip6_output':
/d0/nbsd/netbsd-6/src/sys/netinet6/ip6_output.c:995:20: error: 'ip6f' may be 
used uninitialized in this function
*** [ip6_output.o] Error code 1

nbmake: stopped in 
/d0/nbsd/netbsd-6/obj/i386/sys/arch/i386/compile/NET4501_IPSEC
1 error

nbmake: stopped in 
/d0/nbsd/netbsd-6/obj/i386/sys/arch/i386/compile/NET4501_IPSEC

ERROR: Failed to make all in 
"/d0/nbsd/netbsd-6/src/../obj/i386/sys/arch/i386/compile/NET4501_IPSEC"
*** BUILD ABORTED ***


My configuration for this simple test:

# NET4501_IPSEC - test kernel for IPSEC support

include "arch/i386/conf/NET4501"

options         IPSEC           # IP security
#options        IPSEC_ESP       # IP security (encryption part; define w/IPSEC)
#options        IPSEC_NAT_T     # IPsec NAT traversal (NAT-T)
#options        IPSEC_DEBUG     # debug for IP security


I find this odd because I routinely build other kernel variations
(admittedly based on GENERIC) with IPSEC support enabled for i386,
amd64, sparc, and macppc and have no trouble compiling.  What might I
be missing?  Is it related to NET4501 being non-MODULAR?

I use a tweaked NET4501 kernel w/options IPSEC under 5.1_STABLE and
have no compile-time problems (I've not yet experimented with trying
to use IPSEC, however).

--
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