Under ISE 7.1, I did a simple UART module that has a "terminating character" generic, which is of type character. (When the receiver sees that terminating character, it asserts a "got terminator" output flag.) XST compiled it and the design works well.
I moved to 9.1, and now XST hates the code and craps out:
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- Design Hierarchy Analysis * ========================================================================= Analyzing hierarchy for entity in library (architecture ) with generics. BAUDDIV = 27
Analyzing hierarchy for entity in library (architecture ) with generics. BAUDDIV = 27 ERROR:Xst - Xst_HdlConst_Utility::BitVector2Const : invalid type (char). ERROR:Xst - Xst_Graph2Hdl::CreateConstSource : not implemented yet for no-type. ERROR:Xst:2683 - Unexpected error found while building hierarchy.