v0.8.0

v0.8.0 (2023-04-25)

• Be able to build spt, virtio, muen and xen targets on OpenBSD
  (@adamsteen, #544). This change does not allow us to "run" these targets on
  OpenBSD

• Fix linker scripts with TLS (Thread Local Storage) sections
  (@palainp, @hannesm, @dinosaure, #542)

• Export TLS symbols (@palainp, @hannesm, @dinosaure, #546)
  breaking change due to #542 & #546, tenders must be upgraded. Indeed,
  solo5.0.7.* tenders will not be able to load correctly unikernels compiled
  with solo5.0.8.0. The internal ABI version for solo5-hvt/solo5-spt was
  upgraded accordingly.

  This version implements Thread Local Storage. The user can initialise a TLS
  block with solo5_tls_init on a pointer to solo5_tls_size() free bytes.
  Then, the user is able to set the tp (Thread Pointer) pointer via
  solo5_set_tls_base(solo5_tls_tp_offset(tls_block)). More details are
  available into solo5.h.

  Note: this change does not allow a Solo5 unikernel to use multiple cores! It
  only provides an API required by OCaml 5 / pthread to launch, at most, one
  thread.

• Fix tests reported by NixOS (@greydot, @ehmry, #547)

• Split out the time.c implementation between Muen and HVT
  (@dinosaure, @Kensan, #552)

• User hypercall instead of TSC-based clock when the user asks for the
  wall-clock (@dinosaure, @reynir, #549, #550)

  Note: only hvt & virtio are updated to avoid a clock drift on the wall-clock.
  Indeed, when the unikernel is suspended, the wall-clock is not updated. Muen
  & Xen still use a TSC-based wall-clock. The spt target was already in sync
  with the host's wall-clock.

• Improve the muen clock (@Kensan, #553)

• Fix the .bss section according to #542 & #546. The .bss section is tagged
  with PT_LOAD. Tenders are available to load this section properly.
  (@Kensan, @dinosaure, #551, #554)

• Fix the cross-compilation of Solo5 for aarch64
  (@dinosaure, @palainp, @hannesm, #555)

• Increase the Muen ABI (2 to 3) due to TLS changes (@Kensan, #557)

• Support lifecycle management for Muen (@Kensan, #557)
  The user is able to configure automatic restarting of unikernels that invokes
  solo5_ext()

• Fix the test_fpu test & ensure the alignment of variables (@Kensan, #557)