I have a question about the GameAbilities plugin and the GAS component.

[hy99e]

Gameplay capability spec.h(289): [C4430] no format specifier. Let’s assume int. Note: C++ does not support default int.

Gameplay capability specification: [C2535] ‘FGamePlayabilitySpec::FGameplayAbilitySpec(void)’: A member function has already been defined or declared.

Gameplay capability specification: [C2061] Syntax error: identifier ‘_resharper_unknow_type’

In my own testing, I found that if I checked GameAbilites in the plugin, restarted, generated C++, and then compiled or ran it in the IDE, I would get that error.
After testing in several ways, I found that if I checked GameAbilites, restarted, turned off the editor, and then ran it in the IDE, it worked fine.
And if I created the AbilitySystemComponent and ran it in the IDE, I got that error. So I deleted the AbilitySystemComponent.h and AbilitySystemComponent.cpp files from the IDE directory and ran it again in the IDE and it worked fine.
That’s all the information I got.

[3dRaven]

You were missing header includes in your project. You should have forward declared classes from the GameAbility plugin and then included the needed header files in your cpp file.

The use of GameplayAbilities also requires the module GameplayAbilities inside of your build files dependencies.