Tracking Issue for debuginfo testsuite test infra woes

[jieyouxu]

This is a tracking issue for various problems and deficiencies related to the debuginfo test suite located at tests/debuginfo, mostly on the test-infra side (and not compiler bugs).

Environment control

• Debuginfo tests don't control for ambient tools #126092
• Debuginfo tests are highly sensitive to debugger versions and thus very fragile #133111
• Debuginfo tests sometimes run with the wrong Python version on MacOS #123621

Test coverage issues

• lldb tests only run on macos #81813
• Is anyone running our gdb-based Android debuginfo tests? #129139

Build/bootstrap issues

• Running ./x test tests/debuginfo triggers recompiles for debugger visualizer script changes #133692
• Compiler selects invalid --lldb-python path #69869

compiletest issues

• compiletest: debugger ignore logic papers over debugger failing to init #134469
• The debuginfo test harness does not load pretty-printers for windows-gnu #128981

External issues

LLDB

• Cannot run LLDB API Tests on MacOS llvm/llvm-project#92603
• [lldb] tests errors ModuleNotFoundError: No module named '_lldb' with BuildType=Debug on Windows  llvm/llvm-project#87381

GDB

• Add the GDB pretty-printers to the Windows Rust installation #29658
• rustc failed to pass debuginfo testsuite when using GDB 15 #122751

MSVC

• Improve MSVC debug info for f16 and f128 #121837

Unknown, needs investigation

These bugs may need investigation (is it our compiler bug, our test infra bug, external bug, or a combination of both?).

• gdb on aarch64-unknown-linux-gnu/windows-gnu cannot print unused by-value non-immediate arguments #128973
• Stepping with "next" in a debugger skips past end-of-scope drops #128971 (gdb or our problem?)
• Buggy debuginfo test suite, or just function-names.rs? #126060 (maybe in debuginfo we emit?)
• LLDB tests fail with windows-gnu #77744
• debuginfo function-call test fails on big endian #74884 (endianness problem somewhere?)
• debuginfo test hanging on arm-android #74847 (arm-android, good luck trying to repro this locally)

Possible test infra cleanups/improvements

• compiletest: Less special handling of debugger/test discovery in debuginfo mode #134673
• debuginfo: does the debugger annotations support revisions? #133121
• Share debuginfo testsuite breakpoint setup logic #134684