[clang] [Clang][Sema] Bump the instantiated index when skipping past non-init-captures (PR #110887)

[Younan Zhang via cfe-commits]

https://github.com/zyn0217 created https://github.com/llvm/llvm-project/pull/110887

Otherwise, we would probably have an unmatched instantiated declaration for init-captures when they come after a non-init capture.

No release note because the bug only affects the trunk.

Fixes #110721

>From 0c36520e882767ea478c5bd94c367a8e1029cd93 Mon Sep 17 00:00:00 2001
From: Younan Zhang <zyn7109 at gmail.com>
Date: Thu, 3 Oct 2024 00:45:51 +0800
Subject: [PATCH] [Clang][Sema] Bump the instantiated index when skipping past
 non-init-captures

Otherwise, we would probably have an unmatched instantiated declaration
for init-captures when they come after a non-init capture.
---
 clang/lib/Sema/SemaConcept.cpp              |  1 +
 clang/test/SemaTemplate/concepts-lambda.cpp | 15 +++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/clang/lib/Sema/SemaConcept.cpp b/clang/lib/Sema/SemaConcept.cpp
index 6a1b32598bb4a6..41ca372743d2a5 100644
--- a/clang/lib/Sema/SemaConcept.cpp
+++ b/clang/lib/Sema/SemaConcept.cpp
@@ -728,6 +728,7 @@ bool Sema::addInstantiatedCapturesToScope(
     ValueDecl *CapturedPattern = CapturePattern.getCapturedVar();
 
     if (!CapturedPattern->isInitCapture()) {
+      Instantiated++;
       continue;
     }
 
diff --git a/clang/test/SemaTemplate/concepts-lambda.cpp b/clang/test/SemaTemplate/concepts-lambda.cpp
index 9c5807bbabdcbf..829a71bc703feb 100644
--- a/clang/test/SemaTemplate/concepts-lambda.cpp
+++ b/clang/test/SemaTemplate/concepts-lambda.cpp
@@ -279,3 +279,18 @@ void dependent_capture_packs() {
   L(V<0>{}, V<1>{}, V<2>{})(V<3>{}, V<4>{})(1);
 }
 } // namespace init_captures
+
+namespace GH110721 {
+
+template <int N> void connect() {
+  int x = N, y = N;
+  [x, y = y]()
+    requires requires { x; }
+  {}();
+}
+
+void foo() {
+  connect<42>();
+}
+
+} // namespace GH110721