Mimalloc v3 upgrade

[heimskr]

What does this PR do?

Upgrades mimalloc from v2 to v3.

How did you verify your code works?

[robobun]

^{Updated 7:42 PM PT - Aug 14th, 2025}

❌ @heimskr, your commit 9a9cf0c has 11 failures in Build #23008:

• test/js/node/test/parallel/test-worker-memory.js - code 1 on 🍎 13 aarch64
• test/js/third_party/@duckdb/node-api/duckdb.test.ts - core dumped on 🐧 24.04 aarch64
• test/js/third_party/@duckdb/node-api/duckdb.test.ts - pid 26642 segmentation fault on 🐧 24.04 x64
• test/js/web/fetch/fetch-leak.test.ts - 2 failing on 🐧 12 aarch64
• test/js/web/fetch/fetch-leak.test.ts - 2 failing on 🐧 12 x64
• test/js/node/worker_threads/worker_threads.test.ts - pid 26666 segmentation fault on 🐧 25.04 aarch64
• test/js/node/worker_threads/worker_threads.test.ts - SIGTRAP on 🐧 12 aarch64
• test/js/node/worker_threads/worker_threads.test.ts - pid 26592 segmentation fault on 🐧 24.04 aarch64
• test/js/node/worker_threads/worker_threads.test.ts - pid 28057 segmentation fault on 🐧 3.21 aarch64
• test/js/node/worker_threads/worker_threads.test.ts - pid 28031 segmentation fault on 🐧 3.21 x64
• test/js/node/worker_threads/worker_threads.test.ts - pid 26641 segmentation fault on 🐧 25.04 x64-baseline
• test/js/node/worker_threads/worker_threads.test.ts - pid 26174 segmentation fault on 🐧 12 x64-baseline
• test/js/node/worker_threads/worker_threads.test.ts - pid 26581 segmentation fault on 🐧 24.04 x64-baseline
• test/js/node/worker_threads/worker_threads.test.ts - pid 26635 segmentation fault on 🐧 25.04 x64
• test/js/node/worker_threads/worker_threads.test.ts - pid 26553 segmentation fault on 🐧 24.04 x64
• test/js/node/worker_threads/worker_threads.test.ts - pid 25996 segmentation fault on 🐧 12 x64
• test/js/bun/http/bun-serve-static.test.ts - SIGKILL on 🐧 12 x64-asan
• test/js/bun/http/bun-serve-static.test.ts - SIGKILL on 🐧 25.04 aarch64
• test/js/bun/http/bun-serve-static.test.ts - SIGKILL on 🐧 12 aarch64
• test/js/bun/http/bun-serve-static.test.ts - SIGKILL on 🐧 3.21 x64
• test/js/bun/http/bun-serve-static.test.ts - SIGKILL on 🐧 3.21 aarch64
• test/js/bun/http/bun-serve-static.test.ts - SIGKILL on 🐧 3.21 x64-baseline
• test/js/bun/http/bun-serve-static.test.ts - SIGKILL on 🐧 12 x64-baseline
• test/js/bun/http/bun-serve-static.test.ts - SIGKILL on 🐧 24.04 x64-baseline
• test/js/node/test/parallel/test-child-process-spawnsync-shell.js - timeout on 🪟 2019 x64
• test/js/node/test/parallel/test-child-process-spawnsync-shell.js - timeout on 🪟 2019 x64-baseline
• test/regression/issue/09748.test.ts - pid 5394 error: addresssanitizer on 🐧 12 x64-asan
• annotation error on 🪟 2019 x64-baseline - test-bun
• annotation error on 🪟 2019 x64 - test-bun
• annotation error on 🍎 14 x64 - test-bun
• annotation error on 🐧 25.04 aarch64 - test-bun
• annotation error on 🐧 3.21 aarch64 - test-bun
• annotation error on 🐧 24.04 aarch64 - test-bun
• annotation error on 🐧 12 aarch64 - test-bun
• annotation error on 🐧 3.21 x64 - test-bun
• annotation error on 🐧 3.21 x64-baseline - test-bun
• annotation error on 🐧 25.04 x64-baseline - test-bun
• test/regression/issue/09748.test.ts - pid 8902 segmentation fault on 🐧 12 x64-baseline
• annotation error on 🐧 24.04 x64-baseline - test-bun
• annotation error on 🍎 13 x64 - test-bun
• annotation error on 🐧 25.04 x64 - test-bun
• annotation error on 🐧 24.04 x64 - test-bun
• annotation error on 🐧 12 x64 - test-bun
• annotation error on 🍎 14 aarch64 - test-bun
• annotation error on 🍎 13 aarch64 - test-bun
• test/js/bun/spawn/spawn.test.ts - 1 failing on 🪟 2019 x64-baseline
• test/js/bun/perf/static-initializers.test.ts - 1 failing on 🍎 14 x64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 12 x64-asan
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🍎 14 x64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 24.04 aarch64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 25.04 aarch64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 3.21 aarch64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 12 aarch64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 3.21 x64-baseline
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 3.21 x64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 24.04 x64-baseline
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 25.04 x64-baseline
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 12 x64-baseline
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 24.04 x64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 25.04 x64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🐧 12 x64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🍎 13 x64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🍎 14 aarch64
• test/js/bun/http/bun-serve-file.test.ts - 1 failing on 🍎 13 aarch64
• test/js/bun/shell/pipeline_stack.test.ts - 1 failing on 🪟 2019 x64-baseline
• test/js/bun/shell/pipeline_stack.test.ts - 1 failing on 🪟 2019 x64

---

🧪   To try this PR locally:

bunx bun-pr 21875

That installs a local version of the PR into your bun-21875 executable, so you can run:

bun-21875 --bun