Function definition erroneously not found

[cD1rtX3]

Type: Bug

void a(int *restrict);

void a(int *restrict i) {
    //
}

Extension version: 1.29.2
VS Code version: Code 1.106.3 (bf9252a2fb45be6893dd8870c0bf37e2e1766d61, 2025-11-25T22:28:18.024Z)
OS version: Linux x64 6.8.0-88-generic
Modes:

[cD1rtX3]

Also, as you can see, restrict is the wrong colour in the prototype (grey instead of blue), likely because the parser thinks it's a name.

[bobbrow]

restrict isn't a standard C++ keyword. Is it a language extension or defined somewhere else?

You can try adding it to the list of defines in your configuration in c_cpp_properties.json to make our parser see it as an empty macro instead. (settings reference)

e.g.

//...
{
  "name": "Linux",
  "defines": [ "restrict" ],
  //...
}
//...

[cD1rtX3]

Sorry, this is C code. I forgot this was also a C++ extension.

[bobbrow]

We support C as well. But as far as I'm aware restrict isn't a keyword in C either. The option I suggested also works for C.

[cD1rtX3]

No, it definitely is a C keyword.

[sean-mcmanus]

@cD1rtX3 I've filed a bug on the shared VS component at https://developercommunity.visualstudio.com/t/C-function-definition-not-found-inco/11012140 .

[cD1rtX3]

Does the bug not exist for the C99 standard revision on Visual Studio? I seem to reproduce it just fine at c99 and gnu99 in VS Code.

[sean-mcmanus]

@cD1rtX3 I just mentioned to use C11, because the msvc/cl.exe compiler doesn't have a C99 option so without the C11 option set it'll use some non-compliant version which doesn't support "restrict". I don't think the standard version would be an issue in the fix and it should be fixed for c99 as well.