Objective-C [qoi]: When an class conforms to multiple
protocols that declare the same property of incompatible
types, issue a warning when class implementation synthesizes 
the property. // rdar://13075400


git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@182316 91177308-0d34-0410-b5e6-96231b3b80d8
Warn on and drop dllimport attrs from variable definitions

AsmPrinter::EmitLinkage() does not handle dllimport linkage.  The LLVM
verifier should also be fixed to reject this.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@182320 91177308-0d34-0410-b5e6-96231b3b80d8