Program transformation in the presence of errors
Alex Aiken, Edward L. Wimmers, John H. P. Williams · 1990
Language designers and implementors have avoided specifying and preserving the meaning of programs that produce errors. This is apparently because being forced to preserve error behavior severely limits the scope of program optimization, even for correct programs. However, preserving error behavior is desirable for debugging, and error behavior must be preserved in any language that permits user-generated exceptions.