UE 5.3.2: what's missing in VSCode setup that these errors show up in a brand-new factory-defaults "3rd-person" project?

[meta_leap]

UE5 editor 5.3.2 on Arch Linux here. Runs real nicely! (The standard ZIP redistributable, not the source git repo version.)

Did some Blueprint lessons and docs-reads to familiarize with engine essentials, but knowing C/++, wanted to dive in to coding.

So I go to “New Project”, under “Games” select “Third Person” and “C++” and name it “Tut3” (tutorial thing), open the project in VSCode by double-clicking .../Tut3/Source/Tut3/Tut3Character.h, then open the other .cpp and .h files in its dir, the extensions are there in VSCode, and clangd disabled in favour of MS’ C/C++ thing, but the C/C++ has plenty complaints:

What could still be missing? (Let’s not forget than UE5 editor install procedure anyway ensured it fetches and installs/places all needed deps, apparently even its own clang copy? Anyway, system-wide I’m on gcc (GCC) 13.2.1 20230801 and clang version 16.0.6… since this is on a brand-new machine, VS Code and all extensions are also as up-to-date as it gets.)

What’s funky is that the project anyway

• runs fine in-editor.
• builds successfully in Debug and Development modes (haven’t tried others) for the “FooEditor Game” permutation

So it “technically compiles”, except to MS’ UntelliSense (in this local setup context). The way the VSCode project is prepared/refreshed by the UE5 editor misses something on Linux here. (Evidently not so on Windows, because there’d be plenty of noise about it =) Just what might it be?

[meta_leap]

Here’s another repro with the “First Person” C++ template:

• preset to Desktop / Scalable
• Project Settings / Supported Platforms: select “Linux” only
• do Tools / Refresh Visual Studio Code Project
• then Tools / Open Visual Studio Code
• build action “FooEditor Linux DebugGame Rebuild” succeeds
• but both before and after that nonetheless:

Same situation then: builds fine and runs fine, but project structure / setup misses something for VSCode’s standard C/C++ extension to fully grok it.

[meta_leap]

Final repro example, the factory-defaults “Vehicle” template, same setup (5.3.2, C++, Desktop Scalable, Linux target only, newest version of everything)

• builds successfully via VSCode build action
• doesn’t run in-editor, unlike the BP template: error msgbox says Couldn't spawn player: Failed to spawn player controller
• VSCode error-diagnostics list explodes like so: