On my pmax, I observed the kernel problems shown below while compiling
a kernel based on yesterday's sources. It does not contain any of the
new IPv6 options (e.g. INET6):

k make -k
cc  -O2 -Wall -Werror -Wstrict-prototypes -Wmissing-prototypes  -Wuninitialized -Wpointer-arith -Wno-main -G 0  -mno-abicalls -mno-half-pic -I. -I../../../../arch -I../../../.. -nostdinc -DMIPS1 -DHZ=256 -DMAXUSERS=64 -D_KERNEL -Dpmax  -c ../../../../netinet/tcp_input.c
cc1: warnings being treated as errors
../../../../netinet/tcp_input.c: In function `syn_cache_respond':
../../../../netinet/tcp_input.c:3141: warning: `error' might be used uninitialized in this function
../../../../netinet/tcp_input.c:3147: warning: `th' might be used uninitialized in this function
*** Error code 1 (continuing)
cc  -O2 -Wall -Werror -Wstrict-prototypes -Wmissing-prototypes  -Wuninitialized -Wpointer-arith -Wno-main -G 0  -mno-abicalls -mno-half-pic -I. -I../../../../arch -I../../../.. -nostdinc -DMIPS1 -DHZ=256 -DMAXUSERS=64 -D_KERNEL -Dpmax  -c ../../../../netinet/tcp_output.c
cc1: warnings being treated as errors
../../../../netinet/tcp_output.c: In function `tcp_output':
../../../../netinet/tcp_output.c:302: warning: `error' might be used uninitialized in this function
../../../../netinet/tcp_output.c:304: warning: `ip' might be used uninitialized in this function
../../../../netinet/tcp_output.c:308: warning: `th' might be used uninitialized in this function
../../../../netinet/tcp_output.c:314: warning: `iphdrlen' might be used uninitialized in this function
*** Error code 1 (continuing)
cc  -O2 -Wall -Werror -Wstrict-prototypes -Wmissing-prototypes  -Wuninitialized -Wpointer-arith -Wno-main -G 0  -mno-abicalls -mno-half-pic -I. -I../../../../arch -I../../../.. -nostdinc -DMIPS1 -DHZ=256 -DMAXUSERS=64 -D_KERNEL -Dpmax  -c ../../../../netinet/tcp_subr.c
cc1: warnings being treated as errors
../../../../netinet/tcp_subr.c: In function `tcp_respond':
../../../../netinet/tcp_subr.c:369: warning: `error' might be used uninitialized in this function
../../../../netinet/tcp_subr.c:370: warning: `hlen' might be used uninitialized in this function
../../../../netinet/tcp_subr.c:376: warning: `th' might be used uninitialized in this function
*** Error code 1 (continuing)
cc  -O2 -Wall -Werror -Wstrict-prototypes -Wmissing-prototypes  -Wuninitialized -Wpointer-arith -Wno-main -G 0  -mno-abicalls -mno-half-pic -I. -I../../../../arch -I../../../.. -nostdinc -DMIPS1 -DHZ=256 -DMAXUSERS=64 -D_KERNEL -Dpmax  -c ../../../../netinet/tcp_usrreq.c
cc1: warnings being treated as errors
../../../../netinet/tcp_usrreq.c: In function `tcp_attach':
../../../../netinet/tcp_usrreq.c:694: warning: `tp' might be used uninitialized in this function
*** Error code 1 (continuing)
making sure the kern library is up to date...
`libkern.a' is up to date.
making sure the compat library is up to date...
`libcompat.a' is up to date.
`all' not remade because of errors.

I send this just to current-users instead of as a PR as they may already
have been corrected.

regards
Erik Bertelsen