Pluginterfaces.lib compilation error (win 10, VS 2022)

Developer VST 3 SDK
1

Hi! This is my first time dealing with c++ development and I ran into a problem the first time I tried to compile a project.
First i saw:

Error E0020 identifier "atomic_fetch_add" and "atomic_int_least32_t" is undefined

Then after several attempts to find a solution, I noticed the line:

The contents of <stdatomic.h> are available only with C++23 or later.

I’m confused because I haven’t found almost any information on how to fix it. I can’t choose the c++23 standard in the compiler configuration.
P.S. I tried to compile in the IDE and using cmake in the terminal, but it happens every time.

2

Somehow your installation is wrong or you did use the wrong folder to generate the SDK. <stdatomic.h> is part of c++11 (see Standard library header <stdatomic.h> - cppreference.com).
Which folder do you used for generating the project?
To build the SDK see the instructions here: GitHub - steinbergmedia/vst3sdk: VST 3 Plug-In SDK

1 Like
3

Correct me if I did something wrong:

  1. I created a VST3 folder in the root of one of the hard drive

  2. installed cmake in a subfolder

  3. I put the vst3 sdk folder next to it

  4. using cmake-gui I configured and generated the project (the ‘build’ folder is located inside the ‘vst3sdk’ folder)

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  5. opened the ‘vstsdk.sln’

  6. right clicked on one of plugin example and clicked ‘build’

Once again I will insert what I have at the output

1>The contents of <stdatomic.h> are available only with C++23 or later.
1>E:\VST3\vst3sdk\pluginterfaces\base\funknown.cpp(91,44): error C2061: syntax error: identifier 'atomic_int_least32_t'
1>Done building project "pluginterfaces.vcxproj" -- FAILED.
2>------ Build started: Project: validator, Configuration: Debug x64 ------
2>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Microsoft\VC\v170\Microsoft.CppCommon.targets(1092,5): error MSB6006: "link.exe" exited with code 1104.
2>LINK : fatal error LNK1104: cannot open file '..\..\..\..\lib\Debug\pluginterfaces.lib'
2>Done building project "validator.vcxproj" -- FAILED.
4

same issue here. worked fine with vs 2019. updated to 2022 and got this error out of the box.

“not supported”

<stdatomic.h> is currently supported when compiled as C++ ( /std:c++latest ). It isn’t yet supported when compiled as C ( /std:c11 and /std:c17 )

Fix:

cmake -DSMTG_USE_STDATOMIC_H=OFF .

or

if (MSVC)
set(SMTG_USE_STDATOMIC_H OFF CACHE BOOL “” FORCE)
endif()

5

OK, so it looks like Visual Studio 2022 was updated lately to include this file. We will have a look if this is a cmake issue or if we need to change something. Thanks Mike737 for providing a solution until then.

6

It works! Thanks!

7

I pasted this into the CMakeLists.txt file but it didn’t work:

if (MSVC)
set(SMTG_USE_STDATOMIC_H OFF CACHE BOOL “” FORCE)
endif()

Then I put this:
-DSMTG_USE_STDATOMIC_H=OFF
into the custom build tool command line inside Visual Studio 2022 where it calls cmake. That didn’t work either. I’m not sure what I’m doing wrong here.

Any ideas?

8

Is there a solution for this yet?

Thanks