[clangd] Show argument names for function pointer struct fields (#69011)

Show argument names in signature help when calling a function pointer
struct field.

1 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaCodeComplete.cpp b/clang/lib/Sema/SemaCodeComplete.cpp
index c44be0df..8d75239 100644
--- a/clang/lib/Sema/SemaCodeComplete.cpp
+++ b/clang/lib/Sema/SemaCodeComplete.cpp
@@ -6137,6 +6137,7 @@ ProduceSignatureHelp(Sema &SemaRef, MutableArrayRef<ResultCandidate> Candidates,
 // so that we can recover argument names from it.
 static FunctionProtoTypeLoc GetPrototypeLoc(Expr *Fn) {
   TypeLoc Target;
+
   if (const auto *T = Fn->getType().getTypePtr()->getAs<TypedefType>()) {
     Target = T->getDecl()->getTypeSourceInfo()->getTypeLoc();
 
@@ -6145,6 +6146,11 @@ static FunctionProtoTypeLoc GetPrototypeLoc(Expr *Fn) {
     if (const auto *const VD = dyn_cast<VarDecl>(D)) {
       Target = VD->getTypeSourceInfo()->getTypeLoc();
     }
+  } else if (const auto *ME = dyn_cast<MemberExpr>(Fn)) {
+    const auto *MD = ME->getMemberDecl();
+    if (const auto *FD = dyn_cast<FieldDecl>(MD)) {
+      Target = FD->getTypeSourceInfo()->getTypeLoc();
+    }
   }
 
   if (!Target)