What's the difference between a Debug vs Release Build?

Feb 14, 2004 dotnet visualstudio suggest edit

That’s a question I’ve been asked several times, and to be honest, I really didn’t know all the details. Till now. Read on.

Found a typo or mistake in the post? suggest edit

Comments

26 responses

mcdeeiis • May 10th, 2006
The biggest difference between these is that:
In a debug build the complete symbolic debug information is emitted to help while debugging applications and also the code optimization is not taken into account.
While in release build the symbolic debug info is not emitted and the code execution is optimized.
Also, because the symbolic info is not emitted in a release build, the size of the final executable is lesser than a debug executable.

One can expect to see funny errors in release builds due to compiler optimizations or differences in memory layout or initialization. These are ususally referred to as Release - Only bugs :)

In terms of execution speed, a release executable will execute faster for sure, but not always will this different be significant.
Shirish Kulkarni • August 22nd, 2006
It's observed that some of the MSVC++ calls work find in the debug mode, but fail functionally in the release builds.
These are specifically referring to the FreeExtra call used in our application.
The debug mode shows a clear reducion in the private memory bytes, while release mode, does not show any changes.
Any help / pointers will be appreciatd ...

Regards,
Shirish
Joel • January 8th, 2007
* the sample code below written in VB.NET 2005 shows some of the "release" bug. Code below is working in debug mode but not in release mode.

badtrip!

Dim strdate As String
Dim strdate2 As String
Dim strlast As Integer = 1
strdate = Format(Date.Now, "MM/dd/yyyy").ToString
strdate2 = Format(Date.Now, "MM/dd/yyyy").ToString
If strdate.ToString <> strdate2.ToString Then
If strlast = 0 Then
End
End If
End If
Jay • January 2nd, 2008
in Debug mode the complete debug symbol is emitted so that the code optimization is not taken place
but in release mode the complete debut symbol is not emitted so that code optimization is taken place
adeel • April 22nd, 2008
The debug build is created with some embedded information which allows the debugger to debug the application and exposed the runtime behavior of the application. On the down side, the debug build is a bit slower and inefficient in execution and larger in size.
arun • May 3rd, 2008
the last modifications in the project is stored in release foler why not in debug folder?
subrama • July 8th, 2008
Debug is for everything but Release is for something
dingleberry • August 17th, 2008
Arcane wizardry burn in hell!!!!!!!!!!!!!!!
Deepak • August 18th, 2008
please tell me which is better debug or build
Pandharinath • November 3rd, 2008
I have one question
what is use of symbolic debug information ?
which is in Debug build.
And we can debug the code in Release mode then why symbolic debug information not required?
muthu.amr • February 22nd, 2010
Release mode will execute faster than debug mode and release mode takes lesser size than debug mode.
Radeev • May 26th, 2010
XML Comments and inline comments are removed in released build.
Akshat sharma • June 20th, 2010
When you compile your application in release mode debug information is not generated and this is the option normally used when you want to deploy your application to client.debug mode is heavy since debugging info gets generated and is used while development to find out error in your code.
When we are moving code to production then we make the mode as Release. Because there no debug is required and the execution also very fast in this mode due to the .pdb file formation will not happens.
Prashant Kalmodiya • June 22nd, 2010
Debug build
1. Basically this for developer
2. Complier code optimization is OFF
Release build
1. Basically this for Client to whom you want to distribute the application
2. Complier code optimization is ON
Hasan Dibas • September 4th, 2010
we use Debug during develpment cycle
we use Release To deploy your project
Non-Sense • October 19th, 2010
I think the best difference is the spelling.
Ravinder Dhiman • October 26th, 2010
During the execution of vb.net program if any error produces then in debug version when we try to correct this error then large amount of data is added up into this program to interact with debugger. this large data increases the size of assembly as well as the speed of the program execution become slower.
while in release version such large amount of data is not added up into that program. so in this mode the program can run fastly as stand alone program
kishore • May 24th, 2011
if you compile in debug mode it run slowly but if you run in the release mode it run fast
debug for developer to now what are the error in the program
release for client to check the formance of the program and output coming what he expect or not
Nathon Dalton • June 14th, 2011
In debug mode...
- Some batch optimizers are disabled.
- Additional debugging paths are enabled.
- More memory is used at runtime.
- Scripts & images downloaded from WebResource.axd are not cached.
Hope that helps!
AnilG • September 2nd, 2011
Debug Version is much different than Release.
Debug version contains the symbolic information which is used for debugging purpose only and code optimization is off. This inturn increase the size of the debug. Where as the Release version contains no symbolic information and code optimization is ON. However, both the debug and release versions use the same source files for generating the respective versions, its the symbolic information and optimization that changes the CRC of the output file.
Gary • February 22nd, 2012
By configuration:
Debug version will include debug info, and no optimization;
Release version will not include debug info and has optimization;
By resulted .exe or .dll:
Debug version has a bigger size, and runs slower;
Release version has a smaller size and runs faster in general.
Look at them in a higher level:
They are just the compiled results from two sets of values for compiler/linker parameters.
sowmya m • June 6th, 2012
Thanks Prashant kalmodiya..
Urs is an awesome answer...
Tun • February 19th, 2013
I used to publish the site with debug mode built. Is that wrong ?
Sugu • July 25th, 2013
Hey Mr Mcdeeiis,

Please recheck the comment before posting..

Difference between Debug Vs Release Build from MSDN is below..

The Debug configuration of your program is
compiled with full symbolic debug information and no optimization.
Optimization complicates debugging, because the relationship between
source code and generated instructions is more complex.

The
Release configuration of your program contains no symbolic debug
information and is fully optimized. Debug information can be generated
in PDB files, depending on the compiler options that are used. Creating
PDB files can be very useful if you later have to debug your release
version. See Specify Symbol (.pdb) and Source Files in the Visual Studio Debugger
sst • October 17th, 2013
really u r nonsense only
Ashish Mishra • February 5th, 2015
Correct ..Both have their own rolls & importance...