commit e423f9517081df442095d83106542467aa327633
author Sam McCall <sam.mccall@gmail.com> Sat Nov 20 01:10:30 2021 +0100
committer Copybara-Service <copybara-worker@google.com> Fri Nov 19 16:15:52 2021 -0800
tree 5a02c327dcab3a2a4848e07ee0c9577748a6215e
parent 79b37c84731d40a6e20d66ba44ae0a14d683b7d1

[clangd] Avoid possible crash: apply configuration after binding methods

The configuration may kick off indexing, which may involve sending LSP
messages.
The crash is fiddly to reproduce in a hermetic test (we need background
indexing on without disk storage, and to handle server->client messages
in LSPClient...)

Fixes https://github.com/clangd/clangd/issues/926

GitOrigin-RevId: f764a1a5bd7c281d3d7cc3c6d7f1430711176762

clangd/ClangdLSPServer.cpp

diff --git a/clangd/ClangdLSPServer.cpp b/clangd/ClangdLSPServer.cpp
index 6c000d3..762ca1a 100644
--- a/clangd/ClangdLSPServer.cpp
+++ b/clangd/ClangdLSPServer.cpp
@@ -493,7 +493,6 @@
     Server.emplace(*CDB, TFS, Opts,
                    static_cast<ClangdServer::Callbacks *>(this));
   }
-  applyConfiguration(Params.initializationOptions.ConfigSettings);
 
   Opts.CodeComplete.EnableSnippets = Params.capabilities.CompletionSnippets;
   Opts.CodeComplete.IncludeFixIts = Params.capabilities.CompletionFixes;
@@ -627,6 +626,10 @@
   if (Opts.Encoding)
     Result["offsetEncoding"] = *Opts.Encoding;
   Reply(std::move(Result));
+
+  // Apply settings after we're fully initialized.
+  // This can start background indexing and in turn trigger LSP notifications.
+  applyConfiguration(Params.initializationOptions.ConfigSettings);
 }
 
 void ClangdLSPServer::onInitialized(const InitializedParams &Params) {}