Fails to build from source: buildsystem/compile.sh fails

Description

Trying to build vlc-android from source on a Linux system with current versions of pretty much everything (OpenMandriva Cooker) fails during the buildsystem/compile.sh -l -a arm64-v8a. There are several things that look wrong in compile.sh output:

Building tools
You are ready to build VLC and its contribs
make: *** No rule to make target '.gas'.  Stop.

It then proceeds to download/build gas-preprocessor anyway, so chances are this one is harmless.

Creating makefile...
Bootstrap completed.
make: aarch64-linux-android-gcc: No such file or directory
/bin/sh: line 1: aarch64-linux-android-gcc: command not found
Run "make" to start compilation.

aarch64-linux-android-gcc no longer exists in the NDK. Of course a system wide aarch64-linux-android toolchain can be built, but that is not listed as a dependency for vlc-android anywhere. If I modify my NDK a little by doing cd ndk/21.4.7075529/toolchains/llvm/prebuilt/linux-x86_64/bin ; ln -s aarch64-linux-android30-clang aarch64-linux-android-gcc, the error message goes away

configure: error: Library libebml >= 1.3.6 libmatroska needed for matroska was not found

This one is odd because the libebml build seemed to succeed earlier, and related files do exist:

$ find . -name libebml*
./vlc/contrib/aarch64-linux-android/lib64/pkgconfig/libebml.pc
./vlc/contrib/aarch64-linux-android/lib64/libebml.a
./vlc/contrib/aarch64-linux-android/include/ebml/c/libebml_t.h
./vlc/contrib/contrib-android-aarch64-linux-android/ebml/libebml.a
./vlc/contrib/contrib-android-aarch64-linux-android/ebml/libebml.pc
./vlc/contrib/contrib-android-aarch64-linux-android/ebml/libebml.proj
./vlc/contrib/contrib-android-aarch64-linux-android/ebml/libebml.pc.in
./vlc/contrib/contrib-android-aarch64-linux-android/ebml/ebml/c/libebml_t.h
./vlc/contrib/tarballs/libebml-1.4.2.tar.xz

I haven't had the time to investigate this yet; probably PKG_CONFIG_PATH isn't being set up correctly to detect the libraries the script built earlier?

Expected behavior

Build succeeds, produces vlc APK

Actual behavior

Build fails

Steps to reproduce

export ANDROID_SDK="/path/to/my/android/sdk/installation"
export ANDROID_NDK=$ANDROID_SDK/ndk/21.4.7075529
buildsystem/compile.sh -l -a arm64-v8a

Context

App version

Tried both master and 3.4.x branches

Android version

11.0

Device model

any

App mode

any