I'm relatively new to Kotlin Native, and to learn more about it, I am studying these two tutorials, one from the official JetBrains documentation and the other from the jonnyzzz blog, both focused on creating an application using C Interop and libcurl:
I'm trying to build the above application on Windows 11.
After struggling a little, I finally managed to import the libcurl library in my Kotlin Native project, making it possible to call the relative C functions. So far, so good, but when I try to build the entire project, these are the errors I receive:
e: C:\Users\Nicola\.konan\dependencies\llvm-11.1.0-windows-x64-essentials/bin/clang++ invocation reported errors
The C:\Users\Nicola\.konan\dependencies\llvm-11.1.0-windows-x64-essentials/bin/clang++ command returned non-zero exit code: 1.
output:
lld-link: error: undefined symbol: __declspec(dllimport) curl_easy_strerror
>>> referenced by C:\Users\Nicola\IdeaProjects\SimpleHttpClient\src\nativeMain\kotlin\Main.kt:15
>>> C:\Users\Nicola\AppData\Local\Temp\konan_temp9458678904101419787\result.o:(libcurl_curl_easy_strerror_wrapper33)
lld-link: error: undefined symbol: __declspec(dllimport) curl_easy_init
>>> referenced by C:\Users\Nicola\IdeaProjects\SimpleHttpClient\src\nativeMain\kotlin\Main.kt:15
>>> C:\Users\Nicola\AppData\Local\Temp\konan_temp9458678904101419787\result.o:(libcurl_curl_easy_init_wrapper36)
lld-link: error: undefined symbol: __declspec(dllimport) curl_easy_perform
>>> referenced by C:\Users\Nicola\IdeaProjects\SimpleHttpClient\src\nativeMain\kotlin\Main.kt:15
>>> C:\Users\Nicola\AppData\Local\Temp\konan_temp9458678904101419787\result.o:(libcurl_curl_easy_perform_wrapper37)
lld-link: error: undefined symbol: __declspec(dllimport) curl_easy_cleanup
>>> referenced by C:\Users\Nicola\IdeaProjects\SimpleHttpClient\src\nativeMain\kotlin\Main.kt:15
>>> C:\Users\Nicola\AppData\Local\Temp\konan_temp9458678904101419787\result.o:(libcurl_curl_easy_cleanup_wrapper38)
lld-link: error: undefined symbol: curl_easy_setopt
>>> referenced by C:\Users\Nicola\AppData\Local\Temp\konan_temp9458678904101419787\result.o:(knifunptr_libcurl39_curl_easy_setopt)
clang++: error: linker command failed with exit code 1 (use -v to see invocation)
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':linkDebugExecutableNative'.
> Compilation finished with errors
* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 8s
And this is the code I wrote:
Main.kt:
import libcurl.*
import kotlinx.cinterop.*
fun main(args: Array<String>) {
val curl = curl_easy_init()
if (curl != null) {
curl_easy_setopt(curl, CURLOPT_URL, "http://jonnyzzz.com")
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L)
val res = curl_easy_perform(curl)
if (res != CURLE_OK) {
println("curl_easy_perform() failed ${curl_easy_strerror(res)?.toKString()}")
}
curl_easy_cleanup(curl)
}
}
libcurl.def:
headers = curl/curl.h
headerFilter = curl/*
build.gradle.kts:
plugins {
kotlin("multiplatform") version "1.7.10"
}
group = "me.nicola"
version = "1.0-SNAPSHOT"
repositories {
mavenCentral()
}
kotlin {
val hostOs = System.getProperty("os.name")
val isMingwX64 = hostOs.startsWith("Windows")
val nativeTarget = when {
hostOs == "Mac OS X" -> macosX64("native")
hostOs == "Linux" -> linuxX64("native")
isMingwX64 -> mingwX64("native")
else -> throw GradleException("Host OS is not supported in Kotlin/Native.")
}
nativeTarget.apply {
compilations.getByName("main") {
cinterops {
val libcurl by creating {
val includePath = "C:\\Users\\Nicola\\Documents\\curl-7.87.0\\curl-7.87.0\\include"
defFile(project.file("src/nativeInterop/cinterop/libcurl.def"))
packageName("libcurl")
compilerOpts("-I/$includePath")
includeDirs.allHeaders(includePath)
}
}
}
binaries {
executable {
val buildPath = "C:\\Users\\Nicola\\Documents\\curl-7.87.0\\curl-7.87.0\\builds\\libcurl-vc-x86-release-dll-ipv6-sspi-schannel\\lib\\libcurl.lib"
entryPoint = "main"
linkerOpts(buildPath)
}
}
}
sourceSets {
val nativeMain by getting
val nativeTest by getting
}
}
What am I missing?
Thanks a lot for your precious time.
