Vivado displays the following Critical Warning on constraints followed by comments.
Example constraint that produces this Critical Warning:
This results in the constraint "set_property PACKAGE_PIN E19 [get_ports CLKIN_P]" not being applied.
This syntax is not correct. The issue is that there needs to be a semi-colon after the constraint and before the comment to indicate the end of the Tcl command.
So the constraint and comment should be as follows: