[clang] Add test for CWG1606

[NekoCdr]

https://cplusplus.github.io/CWG/issues/1606.html

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[llvmbot]

@llvm/pr-subscribers-clang

Author: Yuri Istomin (NekoCdr)

Changes

https://cplusplus.github.io/CWG/issues/1606.html

---

Full diff: https://github.com/llvm/llvm-project/pull/87274.diff

2 Files Affected:

• (modified) clang/test/CXX/drs/dr16xx.cpp (+11)
• (modified) clang/www/cxx_dr_status.html (+1-1)

diff --git a/clang/test/CXX/drs/dr16xx.cpp b/clang/test/CXX/drs/dr16xx.cpp
index 766c90d3bc7bda..cf05cc2291e6ff 100644
--- a/clang/test/CXX/drs/dr16xx.cpp
+++ b/clang/test/CXX/drs/dr16xx.cpp
@@ -35,6 +35,17 @@ void g() {
 }
 } // namespace dr1601
 
+namespace dr1606 { // dr1606: 3.1
+#if __cplusplus >= 201103L
+  std::size_t test() {
+    int i = 1;
+    int j = 1;
+    auto f = [=]{ return i + j;};
+    return sizeof(f);
+  }
+#endif
+} // namespace dr1606
+
 namespace dr1611 { // dr1611: dup 1658
   struct A { A(int); };
   struct B : virtual A { virtual void f() = 0; };
diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html
index c20a5d021e9d95..5e1e03dec1d484 100755
--- a/clang/www/cxx_dr_status.html
+++ b/clang/www/cxx_dr_status.html
@@ -9444,7 +9444,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2>
     <td><a href="https://cplusplus.github.io/CWG/issues/1606.html">1606</a></td>
     <td>NAD</td>
     <td><TT>sizeof</TT> closure class</td>
-    <td class="unknown" align="center">Unknown</td>
+    <td class="full" align="center">Clang 3.1</td>
   </tr>
   <tr id="1607">
     <td><a href="https://cplusplus.github.io/CWG/issues/1607.html">1607</a></td>

[Endilll]

LGTM!

Disclosure: me and author extensively reviewed this offline before publishing.

[shafik]

Thank you for the test! LGTM.

Do we also have a test that sizeof([=]{ return i + j;}) should fail as well? Tangentially related to this DR but if we don't we should cover that in our tests someplace.

[shafik]

It looks like we do have a test and it looks like the restriction was lifted in C++20.

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