dlopen failed: cannot locate symbol "__cxa_pure_virtual"

[nikita-skobov]

This is a continuation of #14

I originally filed this same issue in cpal because I tried using cpal android example, as well as the oboe demo in this repository.

I even tried using the prebuilt oboe-demo in the releases (the latest one, 0.4.1), and i am still getting that error where the __cxa_pure_virtual is not found. More details here:

RustAudio/cpal#563

[imxood]

in my android11 project, it is ok after add c++_shared lib.

[katyo]

Should we give up linking with c++ stdlib by default?

[imxood]

Should we give up linking with c++ stdlib by default?

I think it is more appropriate to consider adding a c++ stdlib feature on the ndk side

[katyo]

@imxood Note that oboe crate also may be used without ndk crate, for example shared libs in Rust to use with jvm/flutter apps. Such use case was primary when I created this bindings.

[enfipy]

Should we give up linking with c++ stdlib by default?

I think we have to make this by default. Because we also managed to run an android app only after linking to c++ stdlib.

[sorz]

It surprised me that the same build works on Android 10 but not on 11 & 12 (symbol __cxa_pure_virtual not found).

Turning on the feature shared-stdcxx works for me, while adding cargo:rustc-link-lib=c++_shared failed with compile-time linking error (missing symbol __muloti4).

oboe = { version = "0.5", features = ["shared-stdcxx"] }

I wrote the following Gradle script to copy libc++_shared.so:

tasks.register("copyCppSharedLibrary") {
    val src = android.ndkDirectory
        .resolve("toolchains/llvm/prebuilt")
        .listFiles()
        .first { it.isDirectory }
        .resolve("sysroot/usr/lib/aarch64-linux-android")
    val dst = layout.buildDirectory.dir("rustJniLibs/android/arm64-v8a")
    copy {
        from(src)
        into(dst)
        include("libc++_shared.so")
    }
}.configure {
    dependsOn("cargoBuild")
}

Note that it only copy the aarch64 version.