Is there Visual Studio 2015 Debugging step skipping?

Question

0.00/5 (No votes)

See more:

I installed the new version of Visual Studio Community 2015.

Opened old Visual Studio 2010 projects. They compiled okay. Then when I needed to debug them I found out something strange.

When I try to Step Over(F10) just skips lines of code like they weren't there.

http://i.imgur.com/xB1nGQp.png[^]

For example I start debugging in line 33, then F10 sends me right to line 43.

How is that?

And is it configurable.

Posted 5-Nov-15 4:03am

Zhivko Kabaivanov

Add a Solution

Comments

Krunal Rohit 5-Nov-15 10:09am

Lines 34, 35 are blank,
36 has some calculation,
37 is blank,
38 has condition and that is obviously going for false, hence it will also skip 39,40 and 41,
42 is again blank
and 43 - there you are.

-KR

Zhivko Kabaivanov 5-Nov-15 11:24am

How to disable this skipping?

Richard MacCutchan 5-Nov-15 12:03pm


int result = 1 - 100;
if (result > 0)

Result will never be greater than zero.

Zhivko Kabaivanov 5-Nov-15 12:04pm

I know that
The problem was that Optimized code is skipped.

Richard MacCutchan 5-Nov-15 12:12pm

Which probably means that you are not working on the debug version of your code.

Philippe Mori 5-Nov-15 12:25pm

What would you expect? That code don't even exist in final executable.

Philippe Mori 5-Nov-15 12:22pm

You cannot debug dead code that was removed. If you need to be able to execute some code only when debugging then you condition should not be known at compile time. Typically, that might be done using a static flag inside the class to enable extra code.

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Zhivko Kabaivanov · Accepted Answer · 2015-11-05T06:05:00

Solution 1

This behavior is consistent with debugging optimized code.

You can verify what code was generated by going to Tools -> ILDasm, loading your executable and inspecting that function. Or, while on a breakpoint in the Debugger, Debug -> Windows -> Disassembly (or click Alt+8).

This may be a new feature in 2015, as my 2013 does not optimize that assignment/test out...

Posted 5-Nov-15 6:05am

Zhivko Kabaivanov

Comments

Philippe Mori 5-Nov-15 12:18pm

I would think that any version of Visual Stidio would optimize away such unreachable code when debugging an optimized version of an application.