[llvm-branch-commits] [clang] [Clang] [C++26] Expansion Statements (Part 9: Control Flow) (PR #169688)

[Shafik Yaghmour via llvm-branch-commits]

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@@ -0,0 +1,135 @@
+// RUN: %clang_cc1 %s -std=c++2c -fsyntax-only -fblocks -verify
+
+void g(int);
+
+void label() {
+  template for (auto x : {1, 2}) {
+    invalid1:; // expected-error {{labels are not allowed in expansion statements}}
+    invalid2:; // expected-error {{labels are not allowed in expansion statements}}
+    goto invalid1; // expected-error {{use of undeclared label 'invalid1'}}
+  }
+
+  template for (auto x : {1, 2}) {
+    (void) [] {
+      template for (auto x : {1, 2}) {
+        invalid3:; // expected-error {{labels are not allowed in expansion statements}}
+      }
+      ok:;
+    };
+
+    (void) ^{
+      template for (auto x : {1, 2}) {
+        invalid4:; // expected-error {{labels are not allowed in expansion statements}}
+      }
+      ok:;
+    };
+
+    struct X {
+      void f() {
+        ok:;
+      }
+    };
+  }
+
+  // GNU local labels are allowed.
+  template for (auto x : {1, 2}) {
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shafik wrote:

Looks like gcc does not support this: https://godbolt.org/z/Pz7sdq1Ge

Maybe we want to check w/ them if this was an oversight or not.

https://github.com/llvm/llvm-project/pull/169688