[PATCH] D130260: [clangd] Make forwarding parameter detection logic resilient

[Kadir Cetinkaya via Phabricator via cfe-commits]

kadircet added inline comments.


================
Comment at: clang-tools-extra/clangd/AST.cpp:790
+    // Skip functions with less parameters, they can't be the target.
+    if (Callee->parameters().size() < Parameters.size())
+      return;
----------------
upsj wrote:
> This is not a sufficient check, since the other parameters need not be from an expanded pack.
> Example:
> ```
> void foo(int a, int b);
> int baz(int x, int y);
> template <typename... Args>
> void bar(Args... args) {
>   foo(baz(args, 1)...);
> }
> 
> void foo() {
>   bar(1, 42);
> }
> ```
> Here we shouldn't print a hint at all, but we print `x:` and `y:`
> The important distinction is between `Expr(args...)` and `Expr(args)...`, which can be decided in the instantiated case by the check I implemented in https://reviews.llvm.org/D130259 for all cases, except when `args` only consists of a single element.
yeah that makes sense, added an extra check.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D130260/new/

https://reviews.llvm.org/D130260