[RFC] Fetch gflags dynamically

[jathu]

Summary

I recently learned about FetchContent. This seems like a nicer solution than using submodules. Thoughts?

Test plan

CI

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/11285

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❌ 22 New Failures, 1 Unrelated Failure

As of commit 0ca8d22 with merge base 09a4b9d ():

NEW FAILURES - The following jobs have failed:

• Build documentation / build (buck2) / Build doc (gh)
  RuntimeError: Command docker exec -t ed07aef261f8ed3f2f839e9fce1ca1cc53837f87fd109f008b8f03d98234dc2f /exec failed with exit code 3
• Lint / lintrunner / linux-job (gh)
  >>> Lint for tools/cmake/extract_sources.py:
• pull / android / build-llm-demo / linux-job (gh)
  RuntimeError: Command docker exec -t bf54d20673cc96ad992f51bdce7c54063cbb727c61b20dbb7ac6ff912865bd43 /exec failed with exit code 3
• pull / test-llama-runner-qnn-linux (fp32, qnn_16a16w, qnn) / linux-job (gh)
  RuntimeError: Command docker exec -t f3b9d46bac7280dad0b1ba7a8d4211cb88c86b132afb7d2f745f29c22675f6fd /exec failed with exit code 2
• pull / test-llama-runner-qnn-linux (fp32, qnn_8a8w, qnn) / linux-job (gh)
  RuntimeError: Command docker exec -t 5df5bd337fc4c0a54ab07eca7c1b7633453ef8ce3c65ff6362547b92f550ff2d /exec failed with exit code 2
• pull / test-models-linux-basic (mv3, portable, buck2, linux.2xlarge, executorch-ubuntu-22.04-clang12) / linux-job (gh)
  RuntimeError: Command docker exec -t 5f1c194a41e081ae3248872fd233ca872fdd431c53e18855740850c22fd17af8 /exec failed with exit code 3
• pull / test-models-linux-basic (mv3, xnnpack-quantization-delegation, buck2, linux.2xlarge, executorch-u... / linux-job (gh)
  RuntimeError: Command docker exec -t 7fd18c251632823e0060d767a269d744d10771a439f9e97844e58f82d8be57f5 /exec failed with exit code 3
• pull / test-models-linux-basic (vit, portable, buck2, linux.2xlarge, executorch-ubuntu-22.04-clang12) / linux-job (gh)
  RuntimeError: Command docker exec -t 7ac943776eaaad610ee58fae5b4a15a12628d96106ba20b72a81353ff85dd411 /exec failed with exit code 3
• pull / test-models-linux-basic (vit, xnnpack-quantization-delegation, buck2, linux.2xlarge, executorch-u... / linux-job (gh)
  RuntimeError: Command docker exec -t 491a53e3cda91d3d02a84fa79f5caf97522e5af41f0545ddb2c40a1e99d3f863 /exec failed with exit code 3
• pull / test-static-llama-qnn-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 90ef7aed2fed1bd7b33c965375c5291d0020b65e8c414200a138102770ec2016 /exec failed with exit code 2
• pull / unittest-buck / macos / macos-job (gh)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 3
• trunk / test-demo-backend-delegation (buck2) / linux-job (gh)
  RuntimeError: Command docker exec -t 3589261ea693ca2f1a5403276dddcc5578d52bb8cc7b7fc880c3a4a402d47dab /exec failed with exit code 3
• trunk / test-llama-runner-qnn-linux (fp32, qnn_16a16w, qnn) / linux-job (gh)
  RuntimeError: Command docker exec -t 0dd5bcdb97d454df4c200cf1722ddc1f8f1f4840501c1d7f0af42d1b89f5e8d0 /exec failed with exit code 2
• trunk / test-llama-runner-qnn-linux (fp32, qnn_8a8w, qnn) / linux-job (gh)
  RuntimeError: Command docker exec -t 0cec6ab81e04034e5c00c940a05d7a0bbe4e8ed1da15a57ddbf345f49b496470 /exec failed with exit code 2
• trunk / test-qnn-model (fp32, dl3) / linux-job (gh)
  RuntimeError: Command docker exec -t 623ba9b2350375d87cf66d832c3ea047eac6593a78139923fa6f5becf6d2e4cb /exec failed with exit code 2
• trunk / test-qnn-model (fp32, ic3) / linux-job (gh)
  RuntimeError: Command docker exec -t ade6b4d71d3e81a5b47785fbae4f2de5ba5b35e18ab25075613529c8a605c886 /exec failed with exit code 2
• trunk / test-qnn-model (fp32, ic4) / linux-job (gh)
  RuntimeError: Command docker exec -t 67fc368c8e9ce42cb04e2de68a43e83b96ead1a90d1e877ee599e66956d13f50 /exec failed with exit code 2
• trunk / test-qnn-model (fp32, mb) / linux-job (gh)
  RuntimeError: Command docker exec -t 2515a65700b557b0205299894796e636cb10f2b333cc0cdcb1204fd433b0e7e3 /exec failed with exit code 2
• trunk / test-qnn-model (fp32, mv2) / linux-job (gh)
  RuntimeError: Command docker exec -t 8f605f60e19c5c5a3caf8e3b63a24b3d494548382841b269207f660e37a221d0 /exec failed with exit code 2
• trunk / test-qnn-model (fp32, mv3) / linux-job (gh)
  RuntimeError: Command docker exec -t 65996d44061939b0cf57b6c2438de6656dd47d6f98988b8c0a703d473ffa28d8 /exec failed with exit code 2
• trunk / test-qnn-model (fp32, vit) / linux-job (gh)
  RuntimeError: Command docker exec -t a5afee3ff5fea8f984e8cada890cf0c17533ece948adec66c1c91d4db1d6d6c5 /exec failed with exit code 2
• trunk / test-qnn-model (fp32, w2l) / linux-job (gh)
  RuntimeError: Command docker exec -t 265e4fb2ded687ecd373837d7934559ac95310a5255a6b077c97bc8d5915e8a4 /exec failed with exit code 2

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• trunk / test-llama-runner-linux (fp32, portable, linux.2xlarge, executorch-ubuntu-22.04-clang12) / linux-job (gh) (detected as infra flaky with no log or failing log classifier)

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[jathu]

nit: lets not log, it's too noisy — do we really need to tell them every time?

[larryliu0820]

I think this is very helpful for debugging

[mergennachin]

Why add such as complication? What are we optimizing for? What are the trade-offs?

gflags doesn't seem very large (if you're optimizing for disk space)

[mergennachin]

See some previous context here: #7305

[jathu]

Discussed with @larryliu0820 offline and we decided to punt on this until our buck workflow is removed from cmake.