The IBM Debugger for AIX stops at a source line near where the breakpoint was set . Also, the color of the source lines is sometimes wrong.
Executable code should be blue. Comments should be green. The following incorrectly shows the SUBTRACT in green and the comment in blue. The ADD and MULTIPLY are correct in blue. Not only that, but the debugger wrongly stopped on the comment when a line-breakpoint was set on the SUBTRACT.
ADD 40 TO HOURS.
SUBTRACT 50 FROM DAYS.
* THIS IS A COMMENT
MULTIPLY 60 BY WEEKS.
The .cbl source file differs from the one used at compile time.
Resolving the problem
Be sure the same unmodified source file, such as foobar.cbl, is available at debugging time as was used when you compiled it.