From: Jason Merrill <jason@redhat.com>
Date: Mon, 12 Sep 2022 16:59:46 +0000 (-0400)
Subject: c++: lambda capture of array with deduced bounds [PR106567]
X-Git-Tag: basepoints/gcc-14~4579
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7c989a8ed47228bdd494a2f0d1f6fdd325f953d7;p=thirdparty%2Fgcc.git

c++: lambda capture of array with deduced bounds [PR106567]

We can't use the type of an array variable directly if we haven't deduced
its length yet.

	PR c++/106567

gcc/cp/ChangeLog:

	* lambda.cc (type_deducible_expression_p): Check
	array_of_unknown_bound_p.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp0x/lambda/lambda-array4.C: New test.
---

diff --git a/gcc/cp/lambda.cc b/gcc/cp/lambda.cc
index 3fb98a980578..3ee1fe9489e4 100644
--- a/gcc/cp/lambda.cc
+++ b/gcc/cp/lambda.cc
@@ -198,6 +198,7 @@ type_deducible_expression_p (tree expr)
   tree t = non_reference (TREE_TYPE (expr));
   return (t && TREE_CODE (t) != TYPE_PACK_EXPANSION
 	  && !WILDCARD_TYPE_P (t) && !LAMBDA_TYPE_P (t)
+	  && !array_of_unknown_bound_p (t)
 	  && !type_uses_auto (t));
 }
 
diff --git a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-array4.C b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-array4.C
new file mode 100644
index 000000000000..94ec7f8457ea
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-array4.C
@@ -0,0 +1,29 @@
+// PR c++/106567
+// { dg-do compile { target c++11 } }
+
+template <class V>
+void urgh()
+{
+    const V x[] = {V(0), V(1), V(2), V(0)};
+
+    [&]() {
+        for (auto& v : x) {}
+    }();
+}
+
+void no_urgh()
+{
+    using V = int;
+
+    const V x[] = {V(0), V(1), V(2), V(0)};
+
+    [&]() {
+        for (auto& v : x) {}
+    }();
+}
+
+int main()
+{
+    no_urgh();
+    urgh<int>();
+}