Test that `clangd --check` works at HEAD.

[matanlurey]

trafficstars

Closes https://github.com/flutter/flutter/issues/141641.

Basically, this should verify "it's possible to use VSCode+LSC, at least in theory".

I'm open to writing a test, but given it is a test I'm less sure it's valuable. Feel free to push back.

[matanlurey]

Oh sad, it looks like this won't work out of the box on CI due to RBE stuff?

I[21:02:53.409] Compile command from CDB is: [/b/s/w/ir/cache/builder/src/out/host_debug_unopt] /b/s/w/ir/cache/builder/src/buildtools/linux-x64/reclient/rewrapper --cfg=/b/s/w/ir/cache/builder/src/flutter/build/rbe/rewrapper-linux-x64.cfg --exec_root=/b/s/w/ir/cache/builder/src/ --server_address=unix:///b/s/w/ir/x/w/recipe_cleanup/rbe5tdxl4rl/reproxy.sock --labels=type=compile,compiler=clang,lang=cpp -MMD -MF obj/flutter/assets/assets.asset_manager.o.d -DUSE_OPENSSL=1 -DADDRESS_SANITIZER -DLEAK_SANITIZER -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D_LIBCPP_DISABLE_AVAILABILITY=1 -D_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS -D_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS -D_DEBUG -D_GLIBCXX_DEBUG=1 -DFLUTTER_RUNTIME_MODE_DEBUG=1 -DFLUTTER_RUNTIME_MODE_PROFILE=2 -DFLUTTER_RUNTIME_MODE_RELEASE=3 -DFLUTTER_RUNTIME_MODE_JIT_RELEASE=4 -DDART_LEGACY_API=[[deprecated]] -DFLUTTER_RUNTIME_MODE=1 -DFLUTTER_JIT_RUNTIME=1 -I../.. -Igen -I../../third_party/libcxx/include -I../../third_party/libcxxabi/include -I../../flutter/build/secondary/third_party/libcxx/config -I../../flutter -fno-strict-aliasing -fstack-protector --param=ssp-buffer-size=4 -fno-omit-frame-pointer -gline-tables-only -fsanitize=address -fsanitize=leak -m64 -march=x86-64 -fPIC -pipe -pthread -fcolor-diagnostics -Wall -Wextra -Wendif-labels -Werror -Wno-missing-field-initializers -Wno-unused-parameter -Wno-unused-but-set-parameter -Wno-unused-but-set-variable -Wno-implicit-int-float-conversion -Wno-deprecated-copy -Wno-psabi -Wno-deprecated-literal-operator -Wno-unqualified-std-cast-call -Wno-non-c-typedef-for-linkage -Wno-range-loop-construct -fvisibility=hidden --sysroot=../../build/linux/debian_sid_amd64-sysroot -Wstring-conversion -Wnewline-eof -O0 -g2 -Wunreachable-code -fvisibility-inlines-hidden -fno-rtti -nostdinc++ -nostdinc++ -fvisibility=hidden -fno-exceptions -c -std=c++17 -resource-dir=/b/s/w/ir/cache/builder/src/buildtools/linux-x64/clang/lib/clang/18 -- /b/s/w/ir/cache/builder/src/flutter/assets/asset_manager.cc
I[21:02:53.416] Parsing command...
E[21:02:53.450] [drv_unknown_argument] Line 1: unknown argument: '--cfg=/b/s/w/ir/cache/builder/src/flutter/build/rbe/rewrapper-linux-x64.cfg'
E[21:02:53.451] [drv_unknown_argument] Line 1: unknown argument: '--exec_root=/b/s/w/ir/cache/builder/src/'
E[21:02:53.451] [drv_unknown_argument] Line 1: unknown argument: '--server_address=unix:///b/s/w/ir/x/w/recipe_cleanup/rbe5tdxl4rl/reproxy.sock'
E[21:02:53.451] [drv_unknown_argument] Line 1: unknown argument: '--labels=type=compile,compiler=clang,lang=cpp'

I could try to code to work around this I suppose. Wdut?

[matanlurey]

clangd is getting confused by the RBE prefix. I have no idea if this will help, but it looks like a .clangd file could possibly be taught about how to ignore some flags? https://clangd.llvm.org/config#compileflags

I think the ignored flags might be OK, I am going to try providing --clangd explicitly.

[chinmaygarde]

Triage: We think this is still WIP.

[flutter-dashboard[bot]]

This pull request executed golden file tests, but it has not been updated in a while (20+ days). Test results from Gold expire after as many days, so this pull request will need to be updated with a fresh commit in order to get results from Gold.

[matanlurey]

Ok, sorry for the delay - I revived this PR and tried to make the logic to resolve clangd more robust.

[matanlurey]

Ok I now tried adding two new builders that don't do anything but (hopefully) prepare compile_commands.json ...

[flutter-dashboard[bot]]

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