Mongodb 7.0 RC0 Cycle in dependency graph: LoadICUData

[R_K (Ronald Klop)]

Hi, I’m maintaining some MongoDB ports for FreeBSD.

I accomplished to compile 7.0-RC0. But on first run it crashes.

# mongod --dbpath /var/tmp/mongotest/
{"t":{"$date":"2023-05-02T09:15:47.365Z"},"s":"F",  "c":"CONTROL",  "id":20574,   "ctx":"thread1","msg":"Error during global initialization","attr":{"error":{"code":5,"codeName":"GraphContainsCycle","errmsg":"Cycle in dependency graph: LoadICUData -> LoadIcuPrep -> default -> BeginExpressionRegistration -> addToExpressionParserMap_stdDevSamp -> LoadICUData"}}}

This is all. No files are created in the dbpath. Any thoughts or advice on this? It happens on amd64 as well as on aarch64.

[Mark_Benvenuto]

Thank you for your work on the port.

I am trying to repro this locally but it will take time (small VM). That error usually comes incorrect usage of MONGO_INITIALIZER_GENERAL (and related functions) which want to define a DAG for a list of functions to call at startup. It does a topological sort so it is incompatible with a graph with cycles.

1. What build command were you using? Below is the command I am using (I am building debug to aid troubleshooting) on FreeBSD 13.1-STABLE.

buildscripts/scons.py --cxx-std=20 --disable-warnings-as-errors --dbg=on --opt=off AR=llvm-ar VERBOSE=on --use-sasl-client --ssl CC="clang" CPPPATH="/usr/local/include" CXX="clang++" LIBPATH="/usr/local/lib" VARIANT_DIR=jem --libc++ --ninja --allocator=system

I had to add define into SConstruct for _LIBCPP_ENABLE_CXX20_REMOVED_TYPE_TRAITS to fix an issue in ASIO with the recent upgrade to C++ 20 in the MongoDB source code.

2. Are there any local patches that you may have applied?

Thanks

• Mark

[R_K (Ronald Klop)]

Hi, thanks for your quick reply.

The command I’m using is:

/wrkdirs/usr/ports/databases/mongodb70/work/mongo-r7.0.0-rc0/buildscripts/scons.py	-C /wrkdirs/usr/ports/databases/mongodb70/work/mongo-r7.0.0-rc0 --cxx-std=20  --disable-warnings-as-errors  --libc++  --runtime-hardening=on  --use-system-icu  --use-system-libunwind  --use-system-pcre2  --use-system-snappy  --use-system-stemmer  --use-system-yaml  --use-system-zlib  --use-system-zstd  -j2  AR=llvm-ar  MONGO_VERSION=7.0.0-rc0  VERBOSE=on --use-sasl-client --ssl CC="cc"  CCFLAGS="-O2 -pipe  -fstack-protector-strong -fno-strict-aliasing "  CPPPATH="/usr/local/include"  CXX="c++"  CXXFLAGS="-O2 -pipe -fstack-protector-strong -fno-strict-aliasing  "  LIBPATH="/usr/local/lib"  LINKFLAGS="  -fstack-protector-strong "  PKGCONFIGDIR=""  PREFIX="/usr/local"  destdir=/wrkdirs/usr/ports/databases/mongodb70/work/stage DESTDIR=/wrkdirs/usr/ports/databases/mongodb70/work/stage

And added “# define ASIO_HAS_STD_INVOKE_RESULT” to src/third_party/asio-master/asio/include/asio/detail/config.hpp to make asio compile.

In the meantime I found that mongod runs fine if I don’t use --use-system-* for various libraries. Currently trying to find which use-system was the cause. It runs at least if I disable all of them.

[R_K (Ronald Klop)]

Succeeded in running mongod without errors by removing --use-system-icu from the build parameters.
The port is submitted: https://www.freshports.org/databases/mongodb70/.
Now testing some of you parameters like --ninja and --allocator=system.

What would be the benefits of using those settings?

[Mark_Benvenuto]

I filed two issues: https://jira.mongodb.org/browse/SERVER-76814 (Fix mongodb compilation with libc++) and https://jira.mongodb.org/browse/SERVER-76813 (Fix --use-system-icu) for the issues you identified. The fix for --use-system-icu is in the ticket.

In terms of the two options, --ninja is a useful for developers as it compiles faster then scons. For packaging, It is simpler to just use scons. The --allocator=system tells MongoDB to use system allocator instead of the vendored GPerfTools/tcmalloc. Since FreeBSD uses jemalloc, which is comparable in performance too tcmalloc, you save a tiny bit of binary size by just using it.

• Mark