GDNative unresolved external symbol `godot_instance_from_id`

Godot version

3.3.3 stable

System information

Windows 10, Visual Studio Code

Issue description

Whenever I try to use the godot_instance_from_id function from the GDNative API, the linker is unable to find its external symbol reference, causing the build process to fail.

C:\Users\Sam\Desktop\unresolved_symbol>scons platform=windows
scons: Reading SConscript files ...
scons: done reading SConscript files.
scons: Building targets ...
cl /Fosrc\init.obj /c src\init.cpp /TP /nologo -DWIN32 -D_WIN32 -D_WINDOWS -W3 -GR -D_CRT_SECURE_NO_WARNINGS -EHsc -D_DEBUG -MDd /I. /Igodot-cpp\godot-headers 
/Igodot-cpp\include /Igodot-cpp\include\core /Igodot-cpp\include\gen /Isrc /Z7
init.cpp
link /nologo /dll /out:bin\win64\bullets.dll /implib:bin\win64\bullets.lib /LIBPATH:godot-cpp\bin libgodot-cpp.windows.debug.64.lib /PDB:bin\win64\bullets.pdb 
/DEBUG src\init.obj
   Creazione della libreria bin\win64\bullets.lib e dell'oggetto bin\win64\bullets.exp
init.obj : error LNK2019: riferimento al simbolo esterno godot_instance_from_id non risolto nella funzione "public: class godot::Variant __cdecl SimpleClass::method(class godot::Variant)" (?method@SimpleClass@@QEAA?AVVariant@godot@@V23@@Z)
bin\win64\bullets.dll : fatal error LNK1120: 1 esterni non risolti
scons: *** [bin\win64\bullets.dll] Error 1120
scons: building terminated because of errors.

The function is therefore not really available at the moment.

Steps to reproduce

Create a simple GDNative project following the official README (https://github.com/godotengine/godot-cpp/tree/3.3)
Compile all the needed libraries and dependencies and make sure it succeeds.
Now add this snippet inside the method method of the SimpleClass class:
```
if(godot_instance_from_id(0) != nullptr) {
return "";
}
```
Compile again, the process fails.

This is the SConstruct file I use to build the project, nothing special.

``` #!python import os, subprocess opts = Variables([], ARGUMENTS) # Gets the standard flags CC, CCX, etc. env = DefaultEnvironment() # Define our options opts.Add(EnumVariable('target', "Compilation target", 'debug', ['d', 'debug', 'r', 'release'])) opts.Add(EnumVariable('platform', "Compilation platform", '', ['', 'windows', 'x11', 'linux', 'macos'])) opts.Add(EnumVariable('p', "Compilation target, alias for 'platform'", '', ['', 'windows', 'x11', 'linux', 'macos'])) opts.Add(EnumVariable('macos_arch', "Target architecture for the macOS platform", 'universal', ['universal', 'x86_64', 'arm64'])) opts.Add(BoolVariable('use_llvm', "Use the LLVM / Clang compiler", 'no')) opts.Add(PathVariable('target_path', 'The path where the lib is installed.', 'bin/')) opts.Add(PathVariable('target_name', 'The library name.', 'bullets', PathVariable.PathAccept)) # Local dependency paths, adapt them to your setup godot_headers_path = "godot-cpp/godot-headers/" cpp_bindings_path = "godot-cpp/" cpp_library = "libgodot-cpp" # only support 64 at this time.. bits = 64 # Updates the environment with the option variables. opts.Update(env) # Process some arguments if env['use_llvm']: env['CC'] = 'clang' env['CXX'] = 'clang++' if env['p'] != '': env['platform'] = env['p'] if env['platform'] == '': print("No valid target platform selected.") quit(); # Check our platform specifics if env['platform'] == "macos": env['target_path'] += 'macos' cpp_library += '.osx' if env['macos_arch'] == 'universal': env['target_path'] += '/' env.Append(LINKFLAGS=["-arch", "x86_64", "-arch", "arm64"]) env.Append(CCFLAGS=["-arch", "x86_64", "-arch", "arm64"]) else: env['target_path'] += env['macos_arch'] + '/' env.Append(CCFLAGS = ['-arch', env['macos_arch']]) env.Append(LINKFLAGS = ['-arch', env['macos_arch']]) if env['target'] in ('debug', 'd'): env.Append(CCFLAGS = ['-g','-O2', '-std=c++17']) else: env.Append(CCFLAGS = ['-g','-O3', '-std=c++17']) #env.Append(CCFLAGS=['-std=c++14']) elif env['platform'] in ('x11', 'linux'): env['target_path'] += 'x11/' cpp_library += '.linux' if env['target'] in ('debug', 'd'): env.Append(CCFLAGS = ['-fPIC', '-g3','-Og', '-std=c++17']) else: env.Append(CCFLAGS = ['-fPIC', '-g','-O3', '-std=c++17']) elif env['platform'] == "windows": env['target_path'] += 'win64/' cpp_library += '.windows' # This makes sure to keep the session environment variables on windows, # that way you can run scons in a vs 2017 prompt and it will find all the required tools env.Append(ENV = os.environ) env.Append(CCFLAGS = ['-DWIN32', '-D_WIN32', '-D_WINDOWS', '-W3', '-GR', '-D_CRT_SECURE_NO_WARNINGS']) if env['target'] in ('debug', 'd'): env.Append(CCFLAGS = ['-EHsc', '-D_DEBUG', '-MDd']) env['PDB'] = env['target_path'] + env['target_name'] + '.pdb' else: env.Append(CCFLAGS = ['-O2', '-EHsc', '-DNDEBUG', '-MD']) if env['target'] in ('debug', 'd'): cpp_library += '.debug' else: cpp_library += '.release' cpp_library += '.' + str(bits) # make sure our binding library is properly includes env.Append(CPPPATH=['.', godot_headers_path, cpp_bindings_path + 'include/', cpp_bindings_path + 'include/core/', cpp_bindings_path + 'include/gen/']) env.Append(LIBPATH=[cpp_bindings_path + 'bin/']) env.Append(LIBS=[cpp_library]) # tweak this if you want to use different folders, or more folders, to store your source code in. env.Append(CPPPATH=['src/']) sources = Glob('src/*.cpp') library = env.SharedLibrary(target=env['target_path'] + env['target_name'] , source=sources) Default(library) # Generates help for the -h scons option. Help(opts.GenerateHelpText(env)) ```

Minimal reproduction project

No response

godotengine / godot