MFC EXE (binary) size is 5 times bigger in VS 15.8 (_MSC_VER = 1915)
To recreate this:
1. Create a dialog based, static lib MFC application with
_AFX_NO_MFC_CONTROLS_IN_DIALOGS
and no #include <afxcontrolbars.h>
2. build the release build.
I get a exe file with 1897k.
It was used to be less than 400k before.
The windows SDK ver is 10.0.17134.0
Toolset : VS2017 (v141)
Add Comment
The problem is in lib file 'afxnmcd.lib' from MSVC 14.15.26726
When I put 'afxnmcd.lib' from MSVC 14.13.26128 into 14.15.26726 folder the binary size changed to 350k only.
Hello Risger. Thanks for taking the time to report this issue to us. I’ve filed a bug for this issue on the C++ team here. The status on this Developer Community item will be updated as that bug is looked at. Thanks again for reporting this to us.
I am compiling with Windows SDK 8.1 and have the same problem. In v15.7.6 was normal.
Is there some workaround to that or some additional information needed? I'd love to update to 15.8.4, but it seems like this issue is still present.
Looks like there is still no real solution at this moment. All I can do is repalce it with old lib...and I am not sure any problem will happen with that.
I found an old version of afxnmcd.lib on another computer and copied that into the proper folder, and that does build the EXE size back to normal. It also causes link warnings about *.pdb files that are not found.
I compared the executable files, building using newest vs. older LIB file, and then using string.exe to extract and compare just the strings found inside the executables. This experiment shows something interesting. The larger EXE built with the newer LIB file shows many function names that don't exist in the smaller EXE built with the older LIB. Something in the LIB structure must now be creating unnecessary dependencies across many components and functions that did not exist before.
Again, this experiment is using the same source code, same compiler/linker options, same everything, just swapping the LIB file and Rebuilding All. I wonder if this would be an avenue to diagnose what is going wrong here.
This is indeed a regression in 15.8 and is a high priority issue. We have identified the cause and have a fix ready. We are trying to get the fix in as soon as possible, but I am afraid it is too late for 15.9. Given the impact of this bug, the fix was accelerated and is currently slated for 15.9.1 servicing.
Thank you for reporting and helping us identify the problem.
edit: The fix is coming in 15.9.2.
Update: As a temporary workaround, using VS 15.7 works.
As Norm mentions above, the problem is with the afxnmcd[d].lib LIB files in 15.8; they contain a lot more stuff than they should, thus causing the observed difference.
The latest version not affected by this regression is VS 15.7.6.
It reminds me of the times when this post was released:
https://blogs.msdn.microsoft.com/vcblog/2012/02/06/reducing-the-size-of-statically-linked-mfc-applications-in-vc11/
Hope the issue is resolved soon. Looking forward to use the latest versions again.
Why is the problem not listed in the "Known Issue" lists?
