Link errors when compiling shared lib on windows

[Daniel Fitzpatrick]

I am following this short tutorial on compiling a shared lib:

https://wiki.dlang.org/Call_D_from_Ruby_using_FFI

Because it's on Windows I am using these compiler options:

-shared -m64 -defaultlib=libphobos2.so i.d


However, I am receiving rather a lot of linker errors.  Not sure 
what else to provide the compiler.

i.obj : error LNK2019: unresolved external symbol 
_D3std5stdio4File17LockingTextWriter6__dtorMFNeZv referenced in 
function _D3std5stdio16__T7writelnTAyaZ7writelnFNfAyaZv
i.obj : error LNK2019: unresolved external symbol 
_D3std9exception14ErrnoException6__ctorMFNeAyaAyamZC3std9exception14ErrnoException referenced in function _D3std9exception135__T12errnoEnforceTiVAyaa50_633a5c445c646d64325c77696e646f77735c62696e5c2e2e5c2e2e5c7372635c70686f626f735c7374645c737464696f2e64Vmi2776Z12errnoEnforceFNfiLAyaZi
i.obj : error LNK2019: unresolved external symbol 
_D3std3utf12UTFException7__ClassZ referenced in function 
_D3std3utf98__T13_utfExceptionVE3std8typecons55__T4FlagVAyaa19_7573655265706c6163656d656e744463686172Z4Flagi0Z13_utfExceptionFNaNfAyawZw
i.obj : error LNK2019: unresolved external symbol _d_assert_msg 
referenced in function 
_D3std5stdio4File17LockingTextWriter12__T3putTAyaZ3putMFNfAyaZv
i.obj : error LNK2019: unresolved external symbol 
_D3std9exception14ErrnoException7__ClassZ referenced in function 
_D3std9exception135__T12errnoEnforceTiVAyaa50_633a5c445c646d64325c77696e646f77735c62696e5c2e2e5c2e2e5c7372635c70686f626f735c7374645c737464696f2e64Vmi2776Z12errnoEnforceFNfiLAyaZi
i.obj : error LNK2019: unresolved external symbol _fputc_nolock 
referenced in function 
_D3std5stdio4File17LockingTextWriter10__T3putTwZ3putMFNfwZ12trustedFPUTCFNbNiNeiPS4core4stdc5stdio6_iobufZi
i.obj : error LNK2019: unresolved external symbol fwrite 
referenced in function 
_D3std5stdio21__T13trustedFwriteTaZ13trustedFwriteFNbNiNePOS4core4stdc5stdio6_iobufxAaZm
i.obj : error LNK2019: unresolved external symbol 
_D3std5stdio4File6__dtorMFNfZv referenced in function 
_D3std5stdio16__T7writelnTAyaZ7writelnFNfAyaZv
i.obj : error LNK2019: unresolved external symbol _d_throwc 
referenced in function 
_D3std9exception135__T12errnoEnforceTiVAyaa50_633a5c445c646d64325c77696e646f77735c62696e5c2e2e5c2e2e5c7372635c70686f626f735c7374645c737464696f2e64Vmi2776Z12errnoEnforceFNfiLAyaZi
i.obj : error LNK2019: unresolved external symbol 
_D3std5stdio4File17LockingTextWriter7handle_MFNdNeZPS4core4stdc5stdio6_iobuf referenced in function _D3std5stdio4File17LockingTextWriter10__T3putTwZ3putMFNfwZv
i.obj : error LNK2019: unresolved external symbol _d_newclass 
referenced in function 
_D3std9exception135__T12errnoEnforceTiVAyaa50_633a5c445c646d64325c77696e646f77735c62696e5c2e2e5c2e2e5c7372635c70686f626f735c7374645c737464696f2e64Vmi2776Z12errnoEnforceFNfiLAyaZi
i.obj : error LNK2019: unresolved external symbol _d_assertp 
referenced in function 
_D3std5stdio4File17LockingTextWriter10__T3putTwZ3putMFNfwZv
i.obj : error LNK2019: unresolved external symbol _d_arrayboundsp 
referenced in function 
_D3std5stdio4File17LockingTextWriter10__T3putTwZ3putMFNfwZv
i.obj : error LNK2019: unresolved external symbol 
_D3std5stdio13trustedStdoutFNdNeZS3std5stdio4File referenced in 
function _D3std5stdio16__T7writelnTAyaZ7writelnFNfAyaZv
i.obj : error LNK2019: unresolved external symbol 
_D3std5stdio4File17lockingTextWriterMFNfZS3std5stdio4File17LockingTextWriter referenced in function _D3std5stdio16__T7writelnTAyaZ7writelnFNfAyaZv
i.obj : error LNK2019: unresolved external symbol 
_D3std3utf12isValidDcharFNaNbNiNfwZb referenced in function 
_D3std5stdio4File17LockingTextWriter10__T3putTwZ3putMFNfwZv
i.obj : error LNK2019: unresolved external symbol _aApplycd1 
referenced in function 
_D3std5stdio4File17LockingTextWriter12__T3putTAyaZ3putMFNfAyaZv
i.obj : error LNK2019: unresolved external symbol 
_D3std3utf12UTFException6__ctorMFNaNbNiNfAyaAyamC6object9ThrowableZC3std3utf12UTFException referenced in function _D3std3utf98__T13_utfExceptionVE3std8typecons55__T4FlagVAyaa19_7573655265706c6163656d656e744463686172Z4Flagi0Z13_utfExceptionFNaNfAyawZw
i.obj : error LNK2019: unresolved external symbol _fputwc_nolock 
referenced in function 
_D3std5stdio4File17LockingTextWriter10__T3putTwZ3putMFNfwZ13trustedFPUTWCFNbNiNeiPS4core4stdc5stdio6_iobufZi
LINK : error LNK2001: unresolved external symbol 
_DllMainCRTStartup
i.dll : fatal error LNK1120: 20 unresolved externals
Error: linker exited with status 1120