Option to ignore some of drv_unknown_argument errors

[juxeii]

Is there a way to ignore some compiler arguments to get rid of errors? Example:

[{
  "resource": "/var/fpwork/reiss/gnb/cplane/CP-RT/CP-RT/src/common/types/include/types/nr-rrc/ServingCellConfigCommonSIB.hpp",
  "owner": "_generated_diagnostic_collection_name_#2",
  "code": "drv_unknown_argument",
  "severity": 8,
  "message": "Unknown argument: '-fno-ipa-sra'",
  "source": "clang",
  "startLineNumber": 1,
  "startColumn": 1,
  "endLineNumber": 1,
  "endColumn": 1
}]

Would be great to specify a list of options to ignore...like in this case -fno-ipa-sra.

[HighCommander4]

Please see https://clangd.llvm.org/config.html#remove

[juxeii]

Thx. I created a file .clangd in the project root(where main CMakeLists.txt exists). Contents are:

CompileFlags:                     # Tweak the parse settings
  Remove: -fno-ipa-sra, -fno-ipa-sra

The errors are still popping up. Can you please give an example on how to disable fno-ipa-sra? An example file would be great.

Edit: I was not able to find a template .clangd file in this thread either clik

[HighCommander4]

If there are multiple flags, I believe they need to be enclosed in [], e.g.

CompileFlags:
  Remove: [-fno-ipa-sra, -fno-ipa-sra]

(though there's no reason to put the same flag twice -- maybe that was a typo)

[juxeii]

Thx, that was not a typo, I wanted to see the syntax for list here :) Should there be a log entry of clangd that this config file was loaded? I can only the see that the user yaml loaded: V[09:06:49.968] User config file is /home/reiss/.config/clangd/config.yaml

It would help to debug to see which config files were loaded.

[HighCommander4]

I do see log output like this for the project config file:

V[03:24:33.355] config note at <workspace>/.clangd:1:0: Parsing config fragment

[juxeii]

I do not see this, but your example works anyway. Here is my startup log

I[09:24:00.438] clangd version 13.0.1 (ssh://gitlab@gitlab.dynamic.nsn-net.net/clang/llvm-project f7a4722045180b560f319624b76f9f08ef25daab)
I[09:24:00.439] Features: linux
I[09:24:00.439] PID: 30396
I[09:24:00.439] Working directory: /var/fpwork/reiss/gnb/cplane
I[09:24:00.439] argv[0]: /var/fpwork/reiss/gnb/cplane/sdk/cplane/prefix_root_native/bin/clangd
I[09:24:00.439] argv[1]: -log=verbose
I[09:24:00.439] argv[2]: -pretty
I[09:24:00.439] argv[3]: --background-index
V[09:24:00.439] User config file is /home/reiss/.config/clangd/config.yaml
I[09:24:00.439] Starting LSP over stdin/stdout
V[09:24:00.440] <<< {

[HighCommander4]

I believe config parsing is done lazily, and therefore the "Parsing config fragment" log statements only show up a bit later (after the initialize request, but before "ASTWorker building file" for the first open file).

[juxeii]

Great, found it. There is one little thing though

V[10:18:34.328] config note at /var/fpwork/reiss/gnb/cplane/.clangd:1:0: Parsing config fragment
V[10:18:34.329] config note at /var/fpwork/reiss/gnb/cplane/.clangd:1:0: Parsed 1 fragments from file
V[10:18:34.329] Config fragment: compiling /var/fpwork/reiss/gnb/cplane/.clangd:1 -> 0x00007F80E0001D20 (trusted=false)
V[10:18:34.331] config note at /var/fpwork/reiss/gnb/cplane/CP-RT/CP-RT/.clangd:1:0: Parsing config fragment
V[10:18:34.331] config note at /var/fpwork/reiss/gnb/cplane/CP-RT/CP-RT/.clangd:1:0: Parsed 1 fragments from file
V[10:18:34.331] Config fragment: compiling /var/fpwork/reiss/gnb/cplane/CP-RT/CP-RT/.clangd:1 -> 0x00007F80E0028B90 (trusted=false)

We have a rather bad project structure. One project path lives as a nested one in another path, which leads to the situation that all config files are loaded on the "way up": V[10:18:34.331] config note at /var/fpwork/reiss/gnb/cplane/CP-RT/CP-RT/.clangd:1:0: Parsing config fragment This is the config for the current project. And this V[10:18:34.328] config note at /var/fpwork/reiss/gnb/cplane/.clangd:1:0: Parsing config fragment is the config for a project which happens to live above the current one. Why does clangd look for config files, which exist in a path above the project root? Is there a way to configure the project root and to tell clangd that it should not look for other configs in paths above?

[sam-mccall]

Why does clangd look for config files, which exist in a path above the project root?

Well, that behavior is often what you want! Otherwise if you want config to apply to a whole tree, and then specialize behavior in a subtree, you'd have to repeat the whole config.

You can restrict the parent config file from matching subtrees using If.PathExclude: https://clangd.llvm.org/config#if

[juxeii]

Excellent! BTW: Big thanks for your work. The last time I worked with the extension(9.0), it was very slow on our big code base. The improvements to 13.0 are really great! ;)