E:\test>ocamlopt -verbose hello.ml + ml /nologo /coff /Cp /c /Fo"hello.obj" "D:\DOCUME~1\userr\LOCALS~1\Temp\camlasm38dbd9.asm">NUL + ml /nologo /coff /Cp /c /Fo"D:\DOCUME~1\userr\LOCALS~1\Temp\camlstartup4750a8.obj" "D:\DOCUME~1\userr\LOCALS~1\Temp\camlstartupfcb021.asm">NUL + cl /nologo -D_CRT_SECURE_NO_DEPRECATE /MT /Fe"camlprog.exe" -I"D:\Program Files\Objective Caml\lib" "D:\DOCUME~1\userr\LOCALS~1\Temp\camlstartup4750a8.obj" "D:\Program Files\Objective Caml\lib\std_exit.obj" "hello.obj" "D:\Program Files\Objective Caml\lib\stdlib.lib" "D:\Program Files\Objective Caml\lib\libasmrun.lib" advapi32.lib /link /subsystem:console libasmrun.lib(floats.obj) : error LNK2019: unresolved external symbol __ftol2_sse referenced in function _caml_int_of_float libasmrun.lib(ints.obj) : error LNK2019: unresolved external symbol __ftol2_sse referenced in function _caml_nativeint_format libasmrun.lib(major_gc.obj) : error LNK2019: unresolved external symbol __ftol2_sse referenced in function _caml_major_collection_slice libasmrun.lib(sys.obj) : error LNK2019: unresolved external symbol __stat64i32 referenced in function _stat libasmrun.lib(win32.obj) : error LNK2001: unresolved external symbol __stat64i32 libasmrun.lib(win32.obj) : error LNK2019: unresolved external symbol __findnext64i32 referenced in function _expand_pattern libasmrun.lib(win32.obj) : error LNK2019: unresolved external symbol __findfirst64i32 referenced in function _expand_pattern camlprog.exe : fatal error LNK1120: 4 unresolved externals Error during linking E:\test>ml Microsoft (R) Macro Assembler Version 7.10.3077 Copyright (C) Microsoft Corporation. All rights reserved. usage: ML [ options ] filelist [ /link linkoptions] Run "ML /help" or "ML /?" for more info E:\test>cl Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 13.10.3077 for 80x86 Copyright (C) Microsoft Corporation 1984-2002. All rights reserved. usage: cl [ option... ] filename... [ /link linkoption... ] E:\test>type hello.ml let _ = print_endline "hi" E:\test>ocaml -version The Objective Caml toplevel, version 3.10.0