I attempted to specify an array element past the array size as a variable to watch. Repeatable pop-up: "Visual C++ RTL" - Program: IDE.EXE - "The application requested the runtime to terminate in an unusual way. Please contact the application's support team for more information." Originally the array was already defined and filled with data, but I did not remember its size, and the message pooped up when I specified one element too many. The second time I specified the same string "cum" BEFORE the command "SETARRAY cum" was executed, as a deliberate test to see the failure message. It was accepted as a variable specifiation, and displayed  as its value. Singlestepping worked fine until I executed the SETARRAY command, which caused the same error message pop-up, followed by the usual "notify MS" pop-up. When the pop-ups were closed, the IDE/BDEBUGGER window disappeared, and TCC went to a new prompt. TCC 13.02.35 in stand-alone WinXP home SP3 window.