I would like to use Signal to send status messages from my NAS to my phone.

A well-maintained solution, signal-cli, requires at least Java 21. The

My NAS is a armv7 (ARM Cortex-A15). The only pre-built ARMv7-compatible binary that I could find has a dependency on glibc that is higher (GLIBC_2.18) than what I have installed (2.17).

I've spent most of the past few days trying to cross-compile OpenJDK using the Linaro tool-chain.

The problem that I appear to have come up against is that OpenJDK requires a gcc version greater than 6.0, which builds against lib > 2.17.

Is there any cross-compile tool that will help me to solve this problem? I.e. gcc >= 6.0, libc 2.17.

I'm also open to any other solution that solves my use-case.