I ran into this too. It means your MS SDK is not up to date. 
socklen_t is new. 
You can update from:

 http://www.microsoft.com/msdownload/platformsdk/sdkupdate/


"rmdyer@uncc.edu via RT" wrote:
> 
> Hi,
> 
> I just downloaded version 5-1.3.  When trying to compile the sources under
> Windows XP I get the following compile errors...
> 
> Microsoft (R) Program Maintenance Utility   Version 6.00.8168.0
> Copyright (C) Microsoft Corp 1988-1998. All rights reserved.
> 
>         cl    -I.\..\..\..\include -I.\..\..\..\include\krb5  -DKRB5_PRIVATE=1
> -DWIN32_LEAN_AND_MEAN -DKRB5_DEPRECATED=1 /Od /ZI /MDd -nologo /W3
> -Fdobj\i386\dbg\\ -FD  -Foobj\i386\dbg\\ -c ...
> crc32.c
> c:\temp\krb5-1.3\src\include\k5-int.h(509) : error C2143: syntax error :
> missing ')' before '*'
> c:\temp\krb5-1.3\src\include\k5-int.h(509) : error C2081: 'socklen_t' :
> name in formal parameter list illegal
> c:\temp\krb5-1.3\src\include\k5-int.h(509) : error C2143: syntax error :
> missing '{' before '*'
> c:\temp\krb5-1.3\src\include\k5-int.h(509) : error C2059: syntax error : ')'
> c:\temp\krb5-1.3\src\include\k5-int.h(509) : error C2059: syntax error : ';'
> c:\temp\krb5-1.3\src\include\k5-int.h(1674) : error C2143: syntax error :
> missing ')' before '*'
> c:\temp\krb5-1.3\src\include\k5-int.h(1674) : error C2081: 'socklen_t' :
> name in formal parameter list illegal
> c:\temp\krb5-1.3\src\include\k5-int.h(1674) : error C2143: syntax error :
> missing ';' before '*'
> c:\temp\krb5-1.3\src\include\k5-int.h(1674) : error C2059: syntax error : '*'
> c:\temp\krb5-1.3\src\include\k5-int.h(1674) : error C2059: syntax error : ')'
> c:\temp\krb5-1.3\src\include\k5-int.h(1691) : error C2059: syntax error : '}'
> c:\temp\krb5-1.3\src\include\k5-int.h(1698) : error C2143: syntax error :
> missing ')' before '*'
> c:\temp\krb5-1.3\src\include\k5-int.h(1698) : error C2143: syntax error :
> missing '{' before '*'
> c:\temp\krb5-1.3\src\include\k5-int.h(1698) : error C2059: syntax error : ','
> c:\temp\krb5-1.3\src\include\k5-int.h(1698) : error C2059: syntax error : ')'
> c:\temp\krb5-1.3\src\include\k5-int.h(1721) : error C2143: syntax error :
> missing ')' before '*'
> c:\temp\krb5-1.3\src\include\k5-int.h(1721) : error C2081: 'socklen_t' :
> name in formal parameter list illegal
> c:\temp\krb5-1.3\src\include\k5-int.h(1721) : error C2143: syntax error :
> missing '{' before '*'
> c:\temp\krb5-1.3\src\include\k5-int.h(1721) : error C2059: syntax error : ')'
> c:\temp\krb5-1.3\src\include\k5-int.h(1721) : error C2059: syntax error : ';'
> NMAKE : fatal error U1077: 'cl' : return code '0x2'
> Stop.
> NMAKE : fatal error U1077: '"C:\Program Files\Microsoft Visual
> Studio\VC98\bin\NMAKE.EXE"' : return code '0x2'
> Stop.
> NMAKE : fatal error U1077: '"C:\Program Files\Microsoft Visual
> Studio\VC98\bin\NMAKE.EXE"' : return code '0x2'
> Stop.
> NMAKE : fatal error U1077: '"C:\Program Files\Microsoft Visual
> Studio\VC98\bin\NMAKE.EXE"' : return code '0x2'
> Stop.
> 
> Help is appreciated.
> 
> Thanks,
> 
> Rodney
> 
> Rodney M. Dyer
> Windows Systems Programmer
> Mosaic Computing Group
> William States Lee College of Engineering
> University of North Carolina at Charlotte
> Email: rmdyer@uncc.edu
> Web: http://www.coe.uncc.edu/~rmdyer
> Phone (704)687-3518
> Help Desk Line (704)687-3150
> FAX (704)687-2352
> Office  267 Smith Building
> 
> _______________________________________________
> krb5-bugs mailing list
> krb5-bugs@mit.edu
> http://mailman.mit.edu/mailman/listinfo/krb5-bugs

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