For anyone who is interested, below is the summary of the build issue:

Only "amd64" build is failed because it consumes all disk space in the builder,
after checking the build files, some gcc build logs are filled with 
"AddressSanitizer:DEADLYSIGNAL".

Even the official gcc-10 is failed to build.

The builder is a noble VM, and build environment: focal chroot + built
by sbuild.

Finally we can reproduce this issue locally, and interestingly, this issue only 
happens on AMD CPUs (at least some Ryzen and EPYC CPUs we tried) but not Intel 
CPUs.
I have no idea why it only happens on AMD CPUs, maybe Intel and AMD CPUs handle 
entropy in a different way.

This issue is caused by increasing entropy on the newer kernel:
https://github.com/actions/runner-images/issues/9491#issuecomment-1989718917
But applying the following commit to llvm doesn't fix the build issue:
https://github.com/llvm/llvm-project/commit/fb77ca05ffb4f8e666878f2f6718a9fb4d686839

The above commit moves allocator address to avoid the conflict with
higher entropy.

Reduce the entropy by setting "sudo sysctl vm.mmap_rnd_bits=28" in
launchpad builder (noble VM) fixes the issue.

We need to discuss with LP/foundation teams how to fix this.

** Bug watch added: github.com/actions/runner-images/issues #9491
   https://github.com/actions/runner-images/issues/9491

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https://bugs.launchpad.net/bugs/2054343

Title:
  CVE-2023-4039: ARM64 GCC

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