I used sources from the 2.0 branch checked out about 14:30 GMT and I 
recieved this error when compiling

#   compile  libc/Ovfork.o
/usr/2.0/tools/bin/i386--netbsdelf-gcc   -D_LIBC -DLIBC_SCCS 
-DSYSLIBC_SCCS -D_R
EENTRANT -I/usr/src/lib/libc/include -DHESIOD -DINET6 -DNLS -DYP 
-D__DBINTERFACE
_PRIVATE -DI18NMODULE_MAJOR=4 -I/usr/src/libexec/ld.elf_so 
-I/usr/src/lib/libc/d
lfcn -DCITRUS_ICONV -DWITH_RUNE -I/usr/src/lib/libc -DRESOLVSORT -I. 
-DPOSIX_MIS
TAKE -DPORTMAP -DFLOATING_POINT   -nostdinc -isystem 
/usr/2.0/dist//usr/include 
-c -traditional-cpp  -DALL_STATE -DUSG_COMPAT  
-I/usr/src/lib/libc/arch/i386 -no
stdinc -idirafter /usr/2.0/dist//usr/include 
/usr/src/lib/libc/arch/i386/sys/Ovf
ork.S -o Ovfork.o.tmp
/usr/src/lib/libc/arch/i386/sys/Ovfork.S: Assembler messages:
/usr/src/lib/libc/arch/i386/sys/Ovfork.S:54: Error: unknown pseudo-op: 
`.proc'

*** Failed target:  Ovfork.o
*** Failed command: /usr/2.0/tools/bin/i386--netbsdelf-gcc -D_LIBC 
-DLIBC_SCCS -
DSYSLIBC_SCCS -D_REENTRANT -I/usr/src/lib/libc/include -DHESIOD -DINET6 
-DNLS -D
YP -D__DBINTERFACE_PRIVATE -DI18NMODULE_MAJOR=4 
-I/usr/src/libexec/ld.elf_so -I/
usr/src/lib/libc/dlfcn -DCITRUS_ICONV -DWITH_RUNE -I/usr/src/lib/libc 
-DRESOLVSO
RT -I. -DPOSIX_MISTAKE -DPORTMAP -DFLOATING_POINT -nostdinc -isystem 
/usr/2.0/di
st//usr/include -c -traditional-cpp -DALL_STATE -DUSG_COMPAT 
-I/usr/src/lib/libc
/arch/i386 -nostdinc -idirafter /usr/2.0/dist//usr/include 
/usr/src/lib/libc/arc
h/i386/sys/Ovfork.S -o Ovfork.o.tmp
*** Error code 1

Stop.
nbmake: stopped in /usr/src/lib/libc

*** Failed target:  dependall
*** Failed command: cd /usr/src/lib/libc; /usr/2.0/tools/bin/nbmake 
realall
*** Error code 1

Stop.
nbmake: stopped in /usr/src/lib/libc

*** Failed target:  do-lib-libc
*** Failed command: (cd /usr/src/lib/libc && /usr/2.0/tools/bin/nbmake 
dependall
)
*** Error code 1

Stop.
nbmake: stopped in /usr/src

*** Failed target:  build
*** Failed command: (cd /usr/src && /usr/2.0/tools/bin/nbmake do-lib-libc)
*** Error code 1

Stop.
nbmake: stopped in /usr/src

*** Failed target:  distribution
*** Failed command: (cd /usr/src && /usr/2.0/tools/bin/nbmake 
NOPOSTINSTALL=1 bu
ild)
*** Error code 1

i compiled with 

./build.sh -u -O /usr/2.0/obj -T /usr/2.0/tools -D /usr/2.0/dist/ -R 
/usr/2.0/rel distribution install=/

if anymore information is needed, please let me know.

p.s the system is running a 2.0_BETA kernel:

NetBSD Ithorian.splits.mine.nu 2.0_BETA NetBSD 2.0_BETA (GENERIC) #0: Mon 
Apr 26 08:43:51 UTC 2004  
splitscreen@Ithorian.splits.mine.nu:/usr/2.0/obj/sys/arch/i386/compile/GENERIC 
i386
 --------------------------------------------------------------
splitscreen@splits.mine.nu

"It's not that you should never play with fork(), you just have to be 
cautious. It's kind of like sword-swallowing; if you're careful, you won't 
disembowel yourself." -- Brian "Beej" Hall