IntelliJ applies invalid syntax checking to a Kotlin source file in a Kotlin Native project (using the linuxX64 target) that uses a Kotlin Multiplatform library ( https://gitlab.com/napperley/kmqtt-client ). Both the library and the project use the same Kotlin version (1.4.20). There are no compilation/build issues with the project. When doing a Gradle refresh IntelliJ showed a popup window about the Kotlin Native library being incompatible which is incorrect.

@Artyom Degtyarev [JB] can you please take a look?

👀

I am about to provide some build information that uses Gradle Kotlin DSL. Presumably @Artyom Degtyarev [JB] is familiar with the DSL. In the repositories block a custom Maven repository will need to be added:

maven {
        url = uri("<https://dl.bintray.com/digieng/development>")
    }

After adding the repository the dependency is added. In this case the dependency is applied to the linuxX64 target:

linuxX64("linuxX64") {
        compilations.getByName("main") {
            dependencies {
                val kmqttClientVer = "0.2.1-dev"
                implementation("org.digieng:kmqtt-client:$kmqttClientVer")
            }
            cinterops.create("paho_mqtt") {
                val pahoMqttDir = "${System.getenv("HOME")}/paho_mqtt_c-1.3.7"
                val includeDir = "$pahoMqttDir/include"
                compilerOpts(includeDir)
                extraOpts("-libraryPath", "$pahoMqttDir/lib")
                includeDirs(includeDir)
            }
        }
        // ...
    }

With the library it is recommended to create a definition file called paho_mqtt.def, that is stored in src/nativeInterop/cinterop. Inside the def file add the following:

headers = MQTTClient.h MQTTClientPersistence.h
headerFilter = MQTTClient.h MQTTClientPersistence.h
staticLibraries.linux = libpaho-mqtt3c.a

---
static inline MQTTClient_connectOptions* createMqttConnectionOptions() {
    MQTTClient_connectOptions* options = (MQTTClient_connectOptions*) malloc(sizeof(MQTTClient_connectOptions));
    options->struct_id[0] = 'M';
    options->struct_id[1] = 'Q';
    options->struct_id[2] = 'T';
    options->struct_id[3] = 'C';
    options->struct_version = 6;
    options->reliable = 1;
    options->will = NULL;
    options->username = NULL;
    options->password = NULL;
    options->retryInterval = 0;
    options->ssl = NULL;
    options->serverURIcount = 0;
    options->serverURIs = NULL;
    options->MQTTVersion = MQTTVERSION_DEFAULT;
    options->maxInflightMessages = -1;
    return options;
}

static inline MQTTClient_message* createMqttMessage() {
    MQTTClient_message* msg = (MQTTClient_message*) malloc(sizeof(MQTTClient_message));
    return msg;
}