CMake does not find Visual C++ compiler

Question

After installing Visual Studio 2015 and running CMake on a previous project, CMake errors stating that it could not find the C compiler.

The C compiler ident         


        

Answer 1

Checking CMakeErrors.log in CMakeFiles returned:

C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V140\Platforms\x64\PlatformToolsets\v140_xp\Toolset.targets(36,5): warning MSB8003: Could not find WindowsSdkDir_71A variable from the registry. TargetFrameworkVersion or PlatformToolset may be set to an invalid version number.

The error means that the build tools for XP (v140_xp) are not installed. To fix it I installed the proper feature in Visual Studio 2019 installer under Individual Components tab:

Answer 2

Menu → Visual Studio 2015 → MSBuild Command Prompt for Visual Studio 2015. Then CMake can find cl.exe.

set PATH="c:\Program Files (x86)\Windows Kits\10\bin\10.0.16299.0\x64\";%PATH%

Change the upper path to where your Windows SDK is installed.

CMake can find rc.exe.

cd to the path of CMakeLists.txt and do:

md .build
cd .build
cmake .. -G "Visual Studio 14 2015 Win64" -DCMAKE_BUILD_TYPE=Release
cmake --build .

The param after -G should be fetched by CMake. Use --help; you may or may not have the generator.

Answer 3

I had this issue under Windows 10 when using Visual Studio 2015 Professional, while Visual Studio 2015 Express worked! Under Windows 7, both Visual Studio versions used to work.

New projects created from the Visual Studio 2015 Professional IDE successfully compile, but CMake would fail to find the compiler reporting:

The C compiler identification is unknown
The CXX compiler identification is unknown

I upgraded CMake from 3.4.1 to 3.11.4, and now the problem is gone.

Answer 4

I had a similar problem with the Visual Studio 2017 project generated through CMake. Some of the packages were missing while installing Visual Studio in Desktop development with C++. See snapshot:

Visual Studio 2017 Packages:

Also, upgrade CMake to the latest version.

Answer 5

Make sure you are using the correct version of Visual Studio in the generator. I had incorrectly selected Visual Studio 15 when Visual Studio 14 installed.

Answer 6

I looked in CMakeError.log file and found an error about cannot run 'rc.exe'

I searched and found this answer to copy RC.Exe and RcDll.Dll from the Microsoft SDKs bin to the VC bin, and then CMake worked.

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Edit: The top answer to another question suggests that it's a PATH issue, so it could be enough to ensure the Microsoft SDK bin is in your PATH.