When an unsupported Wait/Loop construct is used with XST, the following error occurs:
"ERROR:Xst:845 - file.vhd line xx: Wait Statement expected after Loop Statement."
Unfortunately, the line number in the error message does not reflect where the error is actually occurring; rather, it indicates only the process that contains the offending statement.
Please refer to the VHDL Language Support/Sequential Circuits section of the XST User Guide for more information about supported Wait constructs. The XST User Guide is available at: