Auto merge of #143002 - Enselic:tests-ui-run-fail-exit-vs-signal, r=petrochenkov

tests: Require `run-fail` ui tests to have an exit code (`SIGABRT` not ok)

And introduce two new directives for ui tests:
* `run-crash`
* `run-fail-or-crash`

Normally a `run-fail` ui test like tests that panic shall not be terminated by a signal like `SIGABRT`. So begin having that as a hard requirement.

Some of our current tests do terminate by a signal/crash however.  Introduce and use `run-crash` for those tests. Note that Windows crashes are not handled by signals but by certain high bits set on the process  exit code. Example exit code for crash on Windows: `0xc000001d` (`STATUS_ILLEGAL_INSTRUCTION`).  Because of this, we define "crash" on all platforms as "not exit with success and not exit with a regular failure code in the range 1..=127".

Some tests behave differently on different targets:
* Targets without unwind support will abort (crash) instead of exit with   failure code 101 after panicking. As a special case, allow crashes for   `run-fail` tests for such targets.
* Different sanitizer implementations handle detected memory problems   differently. Some abort (crash) the process while others exit with   failure code 1. Introduce and use `run-fail-or-crash` for such tests.

This adds further (cc rust-lang/rust#142304, rust-lang/rust#142886) protection against the regression in rust-lang/rust#123733 since that bug also manifested as `SIGABRT` in `tests/ui/panics/panic-main.rs` (shown as `Aborted (core dumped)` in the logs attached to that issue, and I have also been able to reproduce this locally).

### TODO
- [x] **Q:** what about on Windows?
    **A:** we'll treat any exit code outside of 1 - 127 as "crashed", and we'll do the same on unix.
- [x] test all permutations of actual vs expected
    **Done:** See rust-lang/rust#143002 (comment).
- [x] Handle targets without unwind support
- [x] Add `run-fail-or-crash` for some sanitizer tests
- [x] remote-test-client. See rust-lang/rust#143448

### Zulip discussion

See https://rust-lang.zulipchat.com/#narrow/channel/122651-general/topic/compiletest.3A.20terminate.20by.20signal.20vs.20exit.20with.20error/with/525611235

try-job: aarch64-apple
try-job: x86_64-msvc-1
try-job: x86_64-gnu
try-job: dist-i586-gnu-i586-i686-musl
try-job: test-various
try-job: armhf-gnu

Author: bors

src/tests/directives.md

@@ -75,8 +75,10 @@ expectations](ui.md#controlling-passfail-expectations).
 | `check-fail`                | Building (no codegen) should fail           | `ui`, `crashes`                           | N/A             |
 | `build-pass`                | Building should pass                        | `ui`, `crashes`, `codegen`, `incremental` | N/A             |
 | `build-fail`                | Building should fail                        | `ui`, `crashes`                           | N/A             |
-| `run-pass`                  | Running the test binary should pass         | `ui`, `crashes`, `incremental`            | N/A             |
-| `run-fail`                  | Running the test binary should fail         | `ui`, `crashes`                           | N/A             |
+| `run-pass`                  | Program must exit with code `0`             | `ui`, `crashes`, `incremental`            | N/A             |
+| `run-fail`                  | Program must exit with code `1..=127`       | `ui`, `crashes`                           | N/A             |
+| `run-crash`                 | Program must crash                          | `ui`                                      | N/A             |
+| `run-fail-or-crash`         | Program must `run-fail` or `run-crash`      | `ui`                                      | N/A             |
 | `ignore-pass`               | Ignore `--pass` flag                        | `ui`, `crashes`, `codegen`, `incremental` | N/A             |
 | `dont-check-failure-status` | Don't check exact failure status (i.e. `1`) | `ui`, `incremental`                       | N/A             |
 | `failure-status`            | Check                                       | `ui`, `crashes`                           | Any `u16`       |

src/tests/ui.md

@@ -448,7 +448,7 @@ even run the resulting program. Just add one of the following
   - `//@ build-pass` — compilation and linking should succeed but do
     not run the resulting binary.
   - `//@ run-pass` — compilation should succeed and running the resulting
-    binary should also succeed.
+    binary should make it exit with code 0 which indicates success.
 - Fail directives:
   - `//@ check-fail` — compilation should fail (the codegen phase is skipped).
     This is the default for UI tests.
@@ -457,10 +457,20 @@ even run the resulting program. Just add one of the following
     - First time is to ensure that the compile succeeds without the codegen phase
     - Second time is to ensure that the full compile fails
   - `//@ run-fail` — compilation should succeed, but running the resulting
-    binary should fail.
-
-For `run-pass` and `run-fail` tests, by default the output of the program itself
-is not checked.
+    binary should make it exit with a code in the range `1..=127` which
+    indicates regular failure. On targets without unwind support, crashes
+    are also accepted.
+  - `//@ run-crash` — compilation should succeed, but running the resulting
+    binary should fail with a crash. Crashing is defined as "not exiting with
+    a code in the range `0..=127`". Example on Linux: Termination by `SIGABRT`
+    or `SIGSEGV`. Example on Windows: Exiting with the code for
+    `STATUS_ILLEGAL_INSTRUCTION` (`0xC000001D`).
+  - `//@ run-fail-or-crash` — compilation should succeed, but running the
+    resulting binary should either `run-fail` or `run-crash`. Useful if a test
+    crashes on some targets but just fails on others.
+
+For `run-pass`. `run-fail`, `run-crash` and `run-fail-or-crash` tests, by
+default the output of the program itself is not checked.
 
 If you want to check the output of running the program, include the
 `check-run-results` directive. This will check for a `.run.stderr` and