Fix android backtraces

[roblabla]

Fixes #17520

If backtrace_syminfo fails to return the symbol, attempt using backtrace_pcinfo to get it. For whatever reason, this fixes the backtraces on android with PIE.

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @sfackler (or someone else) soon.

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[sfackler]

r? @alexcrichton

[alexcrichton]

Thanks! Could you be sure to enable the various backtrace-related tests for android as well?

[alexcrichton]

Could backtrace-debuginfo.rs also get un-ignored?

[roblabla]

Woops, sorry, I missed it. This should do it.

[alexcrichton]

@bors: r+

Thanks!

[bors]

📌 Commit e307fad has been approved by alexcrichton

[bors]

⌛ Testing commit e307fad with merge 8c7bd997251c42a45ff4e0b1cf6e6444be7c4f4a...

[bors]

💔 Test failed - status-travis

[kennytm]

The run-pass/backtrace.rs and run-pass/backtrace-debuginfo.rs still failed on Android.

[00:58:11] thread 'main' panicked at 'Some tests failed', /checkout/src/tools/compiletest/src/main.rs:323:21
[00:58:11] ---- [run-pass] run-pass/backtrace.rs stdout ----
[00:58:11] 	
[00:58:11] error: test run failed!
[00:58:11] status: exit code: 101
[00:58:11] command: /checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools/x86_64-unknown-linux-gnu/release/remote-test-client run /checkout/obj/build/x86_64-unknown-linux-gnu/test/run-pass/backtrace.stage2-arm-linux-androideabi
[00:58:11] stdout:
[00:58:11] ------------------------------------------
[00:58:11] uploaded "/checkout/obj/build/x86_64-unknown-linux-gnu/test/run-pass/backtrace.stage2-arm-linux-androideabi", waiting for result
[00:58:11] 
[00:58:11] ------------------------------------------
[00:58:11] stderr:
[00:58:11] ------------------------------------------
[00:58:11] thread 'main' panicked at 'bad output: thread 'main' panicked at 'explicit panic', /checkout/src/test/run-pass/backtrace.rs:23:8
[00:58:11] stack backtrace:
[00:58:11]    0: <unknown>
[00:58:11]    1: <unknown>
[00:58:11]    2: <unknown>
[00:58:11]    3: <unknown>
[00:58:11]    4: <unknown>
[00:58:11]    5: <unknown>
[00:58:11]    6: <unknown>
[00:58:11]    7: <unknown>
[00:58:11]    8: <unknown>
[00:58:11]    9: <unknown>
[00:58:11]   10: <unknown>
[00:58:11] ', /checkout/src/test/run-pass/backtrace.rs:58:4
[00:58:11] note: Run with `RUST_BACKTRACE=1` for a backtrace.
[00:58:11] 
[00:58:11] ------------------------------------------
[00:58:11] 
[00:58:11] thread '[run-pass] run-pass/backtrace.rs' panicked at 'explicit panic', /checkout/src/tools/compiletest/src/runtest.rs:2479:8
[00:58:11] note: Run with `RUST_BACKTRACE=1` for a backtrace.
[00:58:11] 
[00:58:11] ---- [run-pass] run-pass/backtrace-debuginfo.rs stdout ----
[00:58:11] 	
[00:58:11] error: test run failed!
[00:58:11] status: exit code: 101
[00:58:11] command: /checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools/x86_64-unknown-linux-gnu/release/remote-test-client run /checkout/obj/build/x86_64-unknown-linux-gnu/test/run-pass/backtrace-debuginfo.stage2-arm-linux-androideabi
[00:58:11] stdout:
[00:58:11] ------------------------------------------
[00:58:11] uploaded "/checkout/obj/build/x86_64-unknown-linux-gnu/test/run-pass/backtrace-debuginfo.stage2-arm-linux-androideabi", waiting for result
[00:58:11] 
[00:58:11] ------------------------------------------
[00:58:11] stderr:
[00:58:11] ------------------------------------------
[00:58:11] thread 'main' panicked at 'trace does not match position list: test case 0
[00:58:11] thread 'main' panicked at 'explicit panic', /checkout/src/test/run-pass/backtrace-debuginfo.rs:79:4
[00:58:11] stack backtrace:
[00:58:11]    0: 0xb6e609f7 - <unknown>
[00:58:11]    1: 0xb6e5a9f7 - <unknown>
[00:58:11]    2: 0xb6e6c50f - <unknown>
[00:58:11]    3: 0xb6e6c1ff - <unknown>
[00:58:11]    4: 0xb6e6cb23 - <unknown>
[00:58:11]    5: 0xb6f2c2cf - <unknown>
[00:58:11]    6: 0xb6f2e6f7 - <unknown>
[00:58:11]    7: 0xb6f2e7b7 - <unknown>
[00:58:11]    8: 0xb6f2eeb3 - <unknown>
[00:58:11]    9: 0xb6eaf61b - <unknown>
[00:58:11]   10: 0xb6e6d92b - <unknown>
[00:58:11]   11: 0xb6d9fb4f - <unknown>
[00:58:11] 
[00:58:11] ---
[00:58:11] backtrace-debuginfo.rs:120
[00:58:11] backtrace-debuginfo.rs:168
[00:58:11] ', /checkout/src/test/run-pass/backtrace-debuginfo.rs:134:4
[00:58:11] note: Run with `RUST_BACKTRACE=1` for a backtrace.
[00:58:11] 
[00:58:11] ------------------------------------------
[00:58:11] 
[00:58:11] thread '[run-pass] run-pass/backtrace-debuginfo.rs' panicked at 'explicit panic', /checkout/src/tools/compiletest/src/runtest.rs:2479:8
[00:58:11] 
[00:58:11] 
[00:58:11] failures:
[00:58:11]     [run-pass] run-pass/backtrace-debuginfo.rs
[00:58:11]     [run-pass] run-pass/backtrace.rs
[00:58:11] 
[00:58:11] test result: �[31mFAILED�(B�[m. 2700 passed; 2 failed; 19 ignored; 0 measured; 0 filtered out

[roblabla]

Anyone know how I can get the tests to run on an android ? When running ./x.py test --target arm-linux-androideabi (with an emulator running), I get the following error : https://gist.github.com/roblabla/cc4a1f6019062eb4fbb0fdd1b1504f29

[Mark-Simulacrum]

I'd try something like ./src/ci/docker/run.sh arm-android.

[alexcrichton]

@bors: retry r-

trying to kick bors...

[aidanhs]

@roblabla have you had a chance to look at the android test failures? Just want to make sure this doesn't get lost.

[roblabla]

I haven't yet. I'll get to it next week, probably.

[carols10cents]

Friendly ping to keep this on your radar @roblabla !

[arielb1]

🕸 This PR had been inactive for 2 weeks. Closing it to keep our queue clean. Feel free to reopen. 🕸