Teach Yourself Borland C++ in 14 Days - portal

NOTE
Using the Debugger
builds. Remember that when you change optimization settings, you
need to do a Build All for all modules to be rebuilt using the new
settings.
The IDE debugger has two primary stepping commands that you can use to aid in your
debugging operations: Step Over and Trace Into. Step Over means to execute the next line
in the source code and pause on the line immediately following. Step Over is sort of a
misnomer. The name would seem to indicate that you can step over a source line and the line
would not be executed. That is not the case, however. Step Over means that the current line
will be executed and any functions that that source line calls will be run at full speed. For
instance, let’s say you have set a breakpoint at a line that calls another function in your
program. When you tell the debugger to step over the function, the debugger executes the
function and stops on the next line. (Contrast this with how Trace Into works, which you’ll
learn about in a minute, and it will make more sense.) To use Step Over to step through your
program, you can either press F8 or choose Run | Step Over from the main menu.
As you step through various source code units in your program, the
Code Editor automatically loads and displays the needed source units if
they are not already open.
The Trace Into command allows you to trace into any functions that are encountered as you
step through your code. Rather than executing the function and returning to the next line
as Step Over does, Trace Into will place the execution point on the first source code line in
the function being called. You can then step through that function line by line using Step
Over or Trace Into as necessary. The keyboard shortcut for Trace Into is F7.
After you have inspected variables and done whatever debugging you need to do, you can
again run the program at full speed by clicking the Run button. The program will then
function as normal until the next breakpoint is encountered.
TIP
If you have enabled the Link Debug Version of VCL Linker option,
when you encounter a VCL method Trace Into will take you into the
VCL source code for that method. Once in the VCL source, you can
inspect whatever variables you need to see. If you turn on this option,
you must do a Build All for it to take effect. As I said earlier, stepping
into the VCL source is of doubtful benefit to most programmers.
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