转自：http://blog.csdn.net/magictong/article/details/6105160

LIBC.lib(crt0dat.obj) : error LNK2008: __cinit already defined in libcmt.lib(crt0dat.obj)
LIBC.lib(crt0dat.obj) : error LNK2008: _malloc already defined in libcmt.lib(crt0dat.obj)
LIBC.lib(crt0dat.obj) : error LNK2008: __exit already defined in libcmt.lib(crt0dat.obj)
LIBC.lib(crt0dat.obj) : error LNK2008: __heap—loc-already defined in libcmt.lib(crt0dat.obj)
LIBC.lib(crt0dat.obj) : error LNK2005: __c_exit already defined in libcmt.lib(crt0dat.obj)
LIBC.lib(crt0dat.obj) : error LNK2005: __C_Exit_Done already defined in libcmt.lib(crt0dat.obj)
LIBC.lib(crt0dat.obj) : error LNK2005: __C_Termination_Done already defined in libcmt.lib(crt0dat.obj)
LIBC.lib(crt0dat.obj) : error LNK2005: __exitflag already defined in libcmt.lib(crt0dat.obj)
LIBC.lib(crt0dat.obj) : error LNK2005: __wpgmptr already defined in libcmt.lib(crt0dat.obj)
LINK : warning LNK4098: defaultlib "LIBC" conflicts with use of other libs; use /NODEFAULTLIB:library

解决方法：08的设置方法如下图所示：打开工程属性对话框，选择链接下Input，在Ignore Specific Library里面输入要忽略的库即可（有多个 的话用逗号隔开）。另外具体这里的话，如果是release版本要忽略LIBCMT.lib，debug版本要忽略LIBCMTD.lib。

Error Message

defaultlib 'library' conflicts with use  of other libs; use /NODEFAULTLIB:library

 

You are trying to link with incompatible libraries.

NoteNote 

The run-time libraries now contain directives to prevent mixing different  types. You will receive this warning if you try to use different types or debug  and non-debug versions of the run-time library in the same program. For example,  if you compiled one file to use one kind of run-time library and another file to  use another kind (for example, single-threaded versus multithreaded) and tried  to link them, you will get this warning. You should compile all source files to  use the same run-time library. See the Use Run-Time Library (/MD, /MT, /LD) compiler options for more  information.

You can use the linker's /VERBOSE:LIB switch to  determine which libraries the linker is searching. If you receive LNK4098 and  want to create an executable file that uses, for example, the single-threaded,  non-debug run-time libraries, use the /VERBOSE:LIB option to find out  which libraries the linker is searching. The linker should print LIBC.lib and  not LIBCMT.lib, MSVCRT.lib, LIBCD.lib, LIBCMTD.lib, or MSVCRTD.lib as the  libraries searched. You can tell the linker to ignore the incorrect run-time  libraries by using /NODEFAULTLIB for each  library you want to ignore.

The table below shows which libraries should be ignored depending on which  run-time library you want to use.

 
To use this run-time libraryIgnore these libraries

Single-threaded (libc.lib)

libcmt.lib, msvcrt.lib, libcd.lib, libcmtd.lib, msvcrtd.lib

Multithreaded (libcmt.lib)

libc.lib, msvcrt.lib, libcd.lib, libcmtd.lib, msvcrtd.lib

Multithreaded using DLL (msvcrt.lib)

libc.lib, libcmt.lib, libcd.lib, libcmtd.lib, msvcrtd.lib

Debug Single-threaded (libcd.lib)

libc.lib, libcmt.lib, msvcrt.lib, libcmtd.lib, msvcrtd.lib

Debug Multithreaded (libcmtd.lib)

libc.lib, libcmt.lib, msvcrt.lib, libcd.lib, msvcrtd.lib

Debug Multithreaded using DLL (msvcrtd.lib)

libc.lib, libcmt.lib, msvcrt.lib, libcd.lib,  libcmtd.lib

For example, if you received this warning and you want to create an  executable file that uses the non-debug, single-threaded version of the run-time  libraries, you could use the following options with the linker: