[libc++][ci] Re-enable the bootstrapping build

[ldionne]

@saugustine This started failing recently and the cause isn't obvious to me -- would you mind taking a look? The issue reproduces locally with

./libcxx/utils/ci/run-buildbot-container
./libcxx/utils/ci/run-buildbot bootstrapping-build # run this from the container

[ldionne]

Gentle ping on this. I'll have to disable the GDB pretty-printers test and re-enable the bootstrapping build configuration if this isn't addressed, cause I really want the bootstrapping build to be tested in CI again by the time we release LLVM 14.

[ldionne]

Mark test as unsupported on Clang 14 for now.

[saugustine]

Hi Louis,

My apologies for missing this when it was sent.

The problem here is that your docker image uses gdb 9.2, which doesn't handle dwarf5 info as generated by clang. You can read some discussion about this here:

https://discourse.llvm.org/t/gdb-10-1-cant-read-clangs-dwarf-v5/6035/11

The resolution of that discussion is that the package maintainer should be sure that clang defaults to a format the system debugger is capable of reading.

So you have two options: Make this build of clang default to dwarf4, or upgrade the docker installed copy of gdb to 10.2 or greater.

Not sure which is the best one for you. But in general this test works fine with newer copies of gdb and newer copies of clang, and disabling it probably isn't quite the right thing to do.

libcxx/test/libcxx/gdb/gdb_pretty_printer_test.sh.cpp

 //===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 // REQUIRES: host-has-gdb-with-python
 // REQUIRES: locale.en_US.UTF-8
 // UNSUPPORTED: libcpp-has-no-localization
 // UNSUPPORTED: c++03
 
+// TODO: Investigate this failure, which happens only with the Bootstrapping build.
+// UNSUPPORTED: clang-14
+
 // RUN: %{cxx} %{flags} %s -o %t.exe %{compile_flags} -g %{link_flags}
 // Ensure locale-independence for unicode tests.
 // RUN: env LANG=en_US.UTF-8 %{gdb} -nx -batch -iex "set autoload off" -ex "source %S/../../../utils/gdb/libcxx/printers.py" -ex "python register_libcxx_printer_loader()" -ex "source %S/gdb_pretty_printer_test.py" %t.exe
 
 #include <bitset>
 #include <deque>
 #include <list>
 #include <map>

libcxx/utils/ci/buildkite-pipeline.yml

agents:
       queue: "libcxx-builders"
       os: "linux"
     retry:
       automatic:
         - exit_status: -1  # Agent was lost
           limit: 2
     timeout_in_minutes: 120
 
-  # # Tests with the various supported ways to build libc++.
-  # TODO: Fix failures with the GDB pretty printers
-  # - label: "Bootstrapping build"
-  #   command: "libcxx/utils/ci/run-buildbot bootstrapping-build"
-  #   artifact_paths:
-  #     - "**/test-results.xml"
-  #   agents:
-  #     queue: "libcxx-builders"
-  #     os: "linux"
-  #   retry:
-  #     automatic:
-  #       - exit_status: -1  # Agent was lost
-  #         limit: 2
-  #   timeout_in_minutes: 120
+  # Tests with the various supported ways to build libc++.
+  - label: "Bootstrapping build"
+    command: "libcxx/utils/ci/run-buildbot bootstrapping-build"
+    artifact_paths:
+      - "**/test-results.xml"
+    agents:
+      queue: "libcxx-builders"
+      os: "linux"
+    retry:
+      automatic:
+        - exit_status: -1  # Agent was lost
+          limit: 2
+    timeout_in_minutes: 120
 
   - label: "Legacy Lit configuration"
     command: "libcxx/utils/ci/run-buildbot legacy-test-config"
     artifact_paths:
       - "**/test-results.xml"
     agents:
       queue: "libcxx-builders"
       os: "linux"