make depend all
                      .
                      .
                      .
cc -c -O -W -Wreturn-type -Wcomment -Wredundant-decls -Wimplicit  -nostdinc -I. -I../.. -I../../sys -I/usr/include -DBURKA -DI486_CPU -DFAT_CURSOR -DXSERVER -DPCVT_FREEBSD=210 -DUCONSOLE -DSYSVMSG -DSYSVSEM -DSYSVSHM -DCOMPAT_43 -DQUOTA -DPROCFS -DNFS -DFFS -DGATEWAY -DINET -DKERNEL -Di386 -DLOAD_ADDRESS=0xF0100000  ../../i386/isa/pcvt/pcvt_drv.c
In file included from ../../i386/isa/pcvt/pcvt_drv.c:84:
../../i386/isa/pcvt/pcvt_hdr.h:1214: conflicting types for `pccnprobe'
../../i386/i386/cons.h:57: previous declaration of `pccnprobe'
../../i386/isa/pcvt/pcvt_hdr.h:1214: warning: redundant redeclaration of `pccnprobe' in same scope
../../i386/i386/cons.h:57: warning: previous declaration of `pccnprobe'
../../i386/isa/pcvt/pcvt_hdr.h:1215: conflicting types for `pccninit'
../../i386/i386/cons.h:58: previous declaration of `pccninit'
../../i386/isa/pcvt/pcvt_hdr.h:1215: warning: redundant redeclaration of `pccninit' in same scope
../../i386/i386/cons.h:58: warning: previous declaration of `pccninit'
../../i386/isa/pcvt/pcvt_hdr.h:1216: conflicting types for `pccnputc'
../../i386/i386/cons.h:61: previous declaration of `pccnputc'
../../i386/isa/pcvt/pcvt_hdr.h:1216: warning: redundant redeclaration of `pccnputc' in same scope
../../i386/i386/cons.h:61: warning: previous declaration of `pccnputc'
../../i386/isa/pcvt/pcvt_hdr.h:1217: conflicting types for `pccngetc'
../../i386/i386/cons.h:59: previous declaration of `pccngetc'
../../i386/isa/pcvt/pcvt_hdr.h:1217: warning: redundant redeclaration of `pccngetc' in same scope
../../i386/i386/cons.h:59: warning: previous declaration of `pccngetc'
../../i386/isa/pcvt/pcvt_drv.c:1191: conflicting types for `pccncheckc'
../../i386/i386/cons.h:60: previous declaration of `pccncheckc'
*** Error code 1

Fix: 

Umm...probably /sys/i386/isa/pcvt/pcvt_hdr.h should be fixed
How-To-Repeat: 
Add pcvt to kernel config and try to compile