warning LNK4075: ignoring '/EDITANDCONTINUE' due to '/OPT:ICF' specification

warning LNK4075: ignoring '/EDITANDCONTINUE' due to '/OPT:ICF' specification

When I porting source code from VC++6 to VC++9 with visual studio 2008, I
have this warning:
warning LNK4075: ignoring '/EDITANDCONTINUE' due to '/OPT:ICF' specification
I don't how to fix this warning. Please can somebody help me? Thanks so much!