Checking if your kit is complete... Looks good Note (probably harmless): No library found for -lm Writing Makefile for Math::SO3 Microsoft (R) Program Maintenance Utility Version 6.00.8168.0 Copyright (C) Microsoft Corp 1988-1998. All rights reserved. cp SO3.pm blib\lib\Math\SO3.pm AutoSplitting blib\lib\Math\SO3.pm (blib\lib\auto\Math\SO3) 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 SO3.xs > SO3.xsc && C:\cpanrun\build\5-10-0\bin\perl.exe -MExtUtils::Command -e mv SO3.xsc SO3.c Please specify prototyping behavior for SO3.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=\"0.90\" -DXS_VERSION=\"0.90\" "-IC:\cpanrun\build\5-10-0\lib\CORE" SO3.c SO3.c SO3.xs(36) : error C2054: expected '(' to follow 'inline' SO3.xs(37) : error C2085: 'my_acos' : not in formal parameter list SO3.xs(37) : error C2143: syntax error : missing ';' before '{' SO3.xs(44) : error C2054: expected '(' to follow 'inline' SO3.xs(45) : error C2085: 'do_turn' : not in formal parameter list SO3.xs(45) : error C2143: syntax error : missing ';' before '{' SO3.xs(251) : error C2054: expected '(' to follow 'inline' SO3.xs(252) : error C2085: 'do_turn_debug' : not in formal parameter list SO3.xs(252) : error C2143: syntax error : missing ';' before '{' SO3.xs(358) : error C2065: 'M_PI' : undeclared identifier SO3.xs(365) : warning C4013: 'do_turn' undefined; assuming extern returning int SO3.xs(721) : warning C4013: 'alloca' undefined; assuming extern returning int SO3.xs(721) : warning C4047: '=' : 'char *' differs in levels of indirection from 'int ' SO3.xs(732) : warning C4013: 'my_acos' undefined; assuming extern returning int NMAKE : fatal error U1077: 'cl' : return code '0x2' Stop.