ccls stuck in "starting"

[dholm]

ccls used to work perfectly for me in Emacs but at some point it stopped working and I have been unable to figure out why. When I open a new cc-mode buffer LSP :: Connected to [ccls:<pid>/starting]. is written to *Messages* with ccls always being in starting.

ccls is running and it doesn't crash as it keeps running with the same pid. I have set ccls-args to '("--log-file=/tmp/ccls.log") and lsp-log-io to t however /tmp/ccls.log is always empty, so are the *ccls* and *ccls::stderr* buffers.

lsp-doctor does not report any errors.

Checking for Native JSON support: OK
Check emacs supports `read-process-output-max': OK
Check `read-process-output-max' default has been changed from 4k: OK
Byte compiled against Native JSON (recompile lsp-mode if failing when Native JSON available): OK
`gc-cons-threshold' increased?: OK
Using gccemacs with emacs lisp native compilation (https://akrl.sdf.org/gccemacs.html): NOT AVAILABLE (OPTIONAL)

If I remove ccls from the path then lsp-mode will pick clangd instead and it will start indexing my code right away.

If I run ccls --index . at the root of my project ccls will start indexing it without issues.

*lsp-log: ccls:<pid>* contains the following (I replaced my project specific paths):

[Trace - 08:28:27 AM] Sending request 'initialize - (1)'.
Params: {
  "processId": null,
  "rootPath": "<project-source-folder>",
  "clientInfo": {
    "name": "emacs",
    "version": "GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.22.30, cairo version 1.15.10)\n of 2021-05-13, modified by Debian"
  },
  "rootUri": "file:///<project-source-folder>",
  "capabilities": {
    "workspace": {
      "workspaceEdit": {
        "documentChanges": true,
        "resourceOperations": [
          "create",
          "rename",
          "delete"
        ]
      },
      "applyEdit": true,
      "symbol": {
        "symbolKind": {
          "valueSet": [
            1,
            2,
            3,
            4,
            5,
            6,
            7,
            8,
            9,
            10,
            11,
            12,
            13,
            14,
            15,
            16,
            17,
            18,
            19,
            20,
            21,
            22,
            23,
            24,
            25,
            26
          ]
        }
      },
      "executeCommand": {
        "dynamicRegistration": false
      },
      "workspaceFolders": true,
      "configuration": true
    },
    "textDocument": {
      "declaration": {
        "linkSupport": true
      },
      "definition": {
        "linkSupport": true
      },
      "implementation": {
        "linkSupport": true
      },
      "typeDefinition": {
        "linkSupport": true
      },
      "synchronization": {
        "willSave": true,
        "didSave": true,
        "willSaveWaitUntil": true
      },
      "documentSymbol": {
        "symbolKind": {
          "valueSet": [
            1,
            2,
            3,
            4,
            5,
            6,
            7,
            8,
            9,
            10,
            11,
            12,
            13,
            14,
            15,
            16,
            17,
            18,
            19,
            20,
            21,
            22,
            23,
            24,
            25,
            26
          ]
        },
        "hierarchicalDocumentSymbolSupport": true
      },
      "formatting": {
        "dynamicRegistration": true
      },
      "rangeFormatting": {
        "dynamicRegistration": true
      },
      "rename": {
        "dynamicRegistration": true,
        "prepareSupport": true
      },
      "codeAction": {
        "dynamicRegistration": true,
        "isPreferredSupport": true,
        "codeActionLiteralSupport": {
          "codeActionKind": {
            "valueSet": [
              "",
              "quickfix",
              "refactor",
              "refactor.extract",
              "refactor.inline",
              "refactor.rewrite",
              "source",
              "source.organizeImports"
            ]
          }
        },
        "resolveSupport": {
          "properties": [
            "edit",
            "command"
          ]
        },
        "dataSupport": true
      },
      "completion": {
        "completionItem": {
          "snippetSupport": false,
          "documentationFormat": [
            "markdown",
            "plaintext"
          ],
          "resolveAdditionalTextEditsSupport": true,
          "insertReplaceSupport": true,
          "resolveSupport": {
            "properties": [
              "documentation",
              "details",
              "additionalTextEdits",
              "command"
            ]
          }
        },
        "contextSupport": true
      },
      "signatureHelp": {
        "signatureInformation": {
          "parameterInformation": {
            "labelOffsetSupport": true
          }
        }
      },
      "documentLink": {
        "dynamicRegistration": true,
        "tooltipSupport": true
      },
      "hover": {
        "contentFormat": [
          "markdown",
          "plaintext"
        ]
      },
      "foldingRange": {
        "dynamicRegistration": true
      },
      "callHierarchy": {
        "dynamicRegistration": false
      },
      "publishDiagnostics": {
        "relatedInformation": true,
        "tagSupport": {
          "valueSet": [
            1,
            2
          ]
        },
        "versionSupport": true
      }
    },
    "window": {
      "workDoneProgress": true
    }
  },
  "initializationOptions": {
    "index": {
      "comments": 1,
      "initialBlacklist": [
        "(<blacklisted-folder>|<other-blacklisted-folder>)"
      ]
    },
    "cacheFormat": "msgpack"
  },
  "workDoneToken": "1"
}