[KOTLIN MULTIPLATFORM] Compilation errors related to Kotlinx.serialization

Description

I am trying to use openapi-generator for a multiplatform project and I started with the petstore api as described in this reddit post. I am unable to run ./gradlew assemble on the multiplatform project and gettin some compilation errors which seems related to Kotlinx.serialization library. I have added the different artifacts and steps followed to reproduce this error.

openapi-generator version

openapi-jar-version: 5.0.1
openapi-jar : https://repo1.maven.org/maven2/org/openapitools/openapi-generator-cli/5.0.1/openapi-generator-cli-5.0.1.jar

OpenAPI declaration file content or url

yaml file : https://raw.githubusercontent.com/openapitools/openapi-generator/master/modules/openapi-generator/src/test/resources/3_0/petstore.yaml

Command line used for generation

java -jar openapi-generator-cli.jar generate -g kotlin -i petstore.yaml --library multiplatform -o /var/tmp/kotlin/

Steps to reproduce

1. Download openapi-generator-cli
2. Download petstore.yaml
3. Update distributionUrl in gradlew-wrapper.properties to distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
4. Update following version in build.gradle

• kotlin_version =1.4.30
• coroutines_version = 1.3.1
• ktor_version = 1.5.1
• kotlinx_version = 1.1.0-rc

5. run ./gradlew version

Related issues/PRs

stacktrace : https://gist.github.com/RahulRvR/cc4e8bc52373baa0862f125da888c09a

Suggest a fix/enhancement

• Could be related to the version of libraries (Kotlinx.serialization, ktor) used while generating the models. Is the possible to update the libraries before generating the code?

Start with the Kotlin multiplatform generator command and the generated project's build.gradle and gradlew-wrapper.properties. Run ./gradlew assemble using the reported Kotlin, coroutines, Ktor, and kotlinx.serialization versions, then inspect the linked stacktrace and compilation errors. Done means the generated petstore project compiles successfully with the documented dependencies.