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Writing Makefile for Math::BigInteger

Microsoft (R) Program Maintenance Utility   Version 6.00.8168.0
Copyright (C) Microsoft Corp 1988-1998. All rights reserved.

cp BigInteger.pod blib\lib\Math\BigInteger.pod
cp BigInteger.pm blib\lib\Math\BigInteger.pm
	C:\cpanrun\build\5-10-0\bin\perl.exe C:\cpanrun\build\5-10-0\lib\ExtUtils\xsubpp  -typemap C:\cpanrun\build\5-10-0\lib\ExtUtils\typemap -typemap typemap  BigInteger.xs > BigInteger.xsc && C:\cpanrun\build\5-10-0\bin\perl.exe -MExtUtils::Command -e mv BigInteger.xsc BigInteger.c
Please specify prototyping behavior for BigInteger.xs (see perlxs manual)
	cl -c    -nologo -GF -W3 -MD -Zi -DNDEBUG -O1 -DWIN32 -D_CONSOLE -DNO_STRICT -DHAVE_DES_FCRYPT -DUSE_SITECUSTOMIZE -DPRIVLIB_LAST_IN_INC -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -DUSE_PERLIO -DPERL_MSVCRT_READFIX -MD -Zi -DNDEBUG -O1    -DVERSION=\"1.01\"  -DXS_VERSION=\"1.01\"  "-IC:\cpanrun\build\5-10-0\lib\CORE"   BigInteger.c
BigInteger.c
BigInteger.c(269) : warning C4101: 'RETVAL' : unreferenced local variable
	cl -c    -nologo -GF -W3 -MD -Zi -DNDEBUG -O1 -DWIN32 -D_CONSOLE -DNO_STRICT -DHAVE_DES_FCRYPT -DUSE_SITECUSTOMIZE -DPRIVLIB_LAST_IN_INC -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -DUSE_PERLIO -DPERL_MSVCRT_READFIX -MD -Zi -DNDEBUG -O1    -DVERSION=\"1.01\"  -DXS_VERSION=\"1.01\"  "-IC:\cpanrun\build\5-10-0\lib\CORE"   bn.c
bn.c
bn.c(96) : warning C4013: 'abort' undefined; assuming extern returning int
bn.c(143) : warning C4013: 'free' undefined; assuming extern returning int
bn.c(166) : warning C4013: 'malloc' undefined; assuming extern returning int
bn.c(177) : warning C4013: 'memset' undefined; assuming extern returning int
bn.c(193) : warning C4013: 'realloc' undefined; assuming extern returning int
bn.c(221) : warning C4013: 'memcpy' undefined; assuming extern returning int
bn.c(893) : warning C4047: 'return' : 'int ' differs in levels of indirection from 'void *'
bn.c(951) : error C2632: 'long' followed by 'long' is illegal
NMAKE : fatal error U1077: 'cl' : return code '0x2'
Stop.