How to analyze unsuccessful builds in the analysis phase? - bazel

Question

A bazel binary that I am building completes unsuccessfully during the analysis phase. What flags and tools can I use to debug why it fails during analysis.
Currently, clean builds return the following output
ERROR: build interrupted
INFO: Elapsed time: 57.819 s
FAILED: Build did NOT complete successfully (133 packages loaded)
If I retry building after failed completion, I receive the following output
ERROR: build interrupted
INFO: Elapsed time: 55.514 s
FAILED: Build did NOT complete successfully (68 packages loaded)
What flags can I use to identify
what packages are being loaded
what package the build is being interrupted on
whether the interruption is coming from a timeout or an external process.
Essentially, something similar to --verbose_failures but for the analysis phase rather than the execution phrase.
So far I have ran my build through the build profiler, and have not been able to glean any insight. Here is the output of my build:
WARNING: This information is intended for consumption by Blaze developers only, and may change at any time. Script against it at your own risk
INFO: Loading /<>/result
INFO: bazel profile for <> at Mon Jun 04 00:10:11 GMT 2018, build ID: <>, 49405 record(s)
INFO: Aggregating task statistics
=== PHASE SUMMARY INFORMATION ===
Total launch phase time 9.00 ms 0.02%
Total init phase time 91.0 ms 0.16%
Total loading phase time 1.345 s 2.30%
Total analysis phase time 57.063 s 97.53%
Total run time 58.508 s 100.00%
=== INIT PHASE INFORMATION ===
Total init phase time 91.0 ms
Total time (across all threads) spent on:
Type Total Count Average
=== LOADING PHASE INFORMATION ===
Total loading phase time 1.345 s
Total time (across all threads) spent on:
Type Total Count Average
CREATE_PACKAGE 0.67% 9 3.55 ms
VFS_STAT 0.69% 605 0.05 ms
VFS_DIR 0.96% 255 0.18 ms
VFS_OPEN 2.02% 8 12.1 ms
VFS_READ 0.00% 5 0.01 ms
VFS_GLOB 23.74% 1220 0.93 ms
SKYFRAME_EVAL 24.44% 3 389 ms
SKYFUNCTION 36.95% 8443 0.21 ms
SKYLARK_LEXER 0.19% 31 0.29 ms
SKYLARK_PARSER 0.68% 31 1.04 ms
SKYLARK_USER_FN 0.03% 5 0.27 ms
SKYLARK_BUILTIN_FN 5.91% 349 0.81 ms
=== ANALYSIS PHASE INFORMATION ===
Total analysis phase time 57.063 s
Total time (across all threads) spent on:
Type Total Count Average
CREATE_PACKAGE 0.30% 138 3.96 ms
VFS_STAT 0.05% 2381 0.03 ms
VFS_DIR 0.19% 1020 0.35 ms
VFS_OPEN 0.04% 128 0.61 ms
VFS_READ 0.00% 128 0.01 ms
VFS_GLOB 0.92% 3763 0.45 ms
SKYFRAME_EVAL 31.13% 1 57.037 s
SKYFUNCTION 65.21% 32328 3.70 ms
SKYLARK_LEXER 0.01% 147 0.10 ms
SKYLARK_PARSER 0.03% 147 0.39 ms
SKYLARK_USER_FN 0.20% 343 1.08 ms
As far as my command, I am running
bazel build src:MY_TARGET --embed_label MY_LABEL --stamp --show_loading_progress

Answer 1

Use the --host_jvm_debug startup flag to debug Bazel itself during a build.
From https://bazel.build/contributing.html:
Debugging Bazel
Start creating a debug configuration for both C++ and
Java in your .bazelrc with the following:
build:debug -c dbg
build:debug --javacopt="-g"
build:debug --copt="-g"
build:debug --strip="never"
Then you can rebuild Bazel with bazel build --config debug //src:bazel and use your favorite debugger to start debugging.
For debugging the C++ client you can just run it from gdb or lldb as
you normally would. But if you want to debug the Java code, you must
attach to the server using the following:
Run Bazel with debugging option --host_jvm_debug before the command (e.g., bazel --batch --host_jvm_debug build //src:bazel).
Attach a debugger to the port 5005. With jdb for instance, run jdb -attach localhost:5005. From within Eclipse, use the remote
Java application launch configuration.
Our IntelliJ plugin has built-in debugging support