From: Nathan Sidwell <nathan@acm.org>
Date: Wed, 15 Nov 2017 13:18:09 +0000 (+0000)
Subject: [PR c++/81574] lambda capture of function reference
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=03ab2eb725851203ccc34ca3210439801812a6be;p=gcc.git

[PR c++/81574] lambda capture of function reference

https://gcc.gnu.org/ml/gcc-patches/2017-11/msg01200.html
	PR c++/81574
	* lambda.c (lambda_capture_field_type): Function references are
	always catured by reference.

	PR c++/81574
	* g++.dg/cpp1y/pr81574.C: New.

From-SVN: r254768
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 839042e48c6..e8c882f2253 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2017-11-15  Nathan Sidwell  <nathan@acm.org>
+
+	PR c++/81574
+	* lambda.c (lambda_capture_field_type): Function references are
+	always catured by reference.
+
 2017-11-15  Martin Liska  <mliska@suse.cz>
 
 	* decl.c (begin_destructor_body): Use cp_build_fold_indirect_ref
diff --git a/gcc/cp/lambda.c b/gcc/cp/lambda.c
index 2cbad878ff6..4480c67dc5f 100644
--- a/gcc/cp/lambda.c
+++ b/gcc/cp/lambda.c
@@ -245,7 +245,8 @@ lambda_capture_field_type (tree expr, bool explicit_init_p,
     {
       type = non_reference (unlowered_expr_type (expr));
 
-      if (!is_this && by_reference_p)
+      if (!is_this
+	  && (by_reference_p || TREE_CODE (type) == FUNCTION_TYPE))
 	type = build_reference_type (type);
     }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 1dada439faf..8478a7a88f2 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2017-11-15  Nathan Sidwell  <nathan@acm.org>
+
+	PR c++/81574
+	* g++.dg/cpp1y/pr81574.C: New.
+
 2017-11-15  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/82985
diff --git a/gcc/testsuite/g++.dg/cpp1y/pr81574.C b/gcc/testsuite/g++.dg/cpp1y/pr81574.C
new file mode 100644
index 00000000000..f9949ab90e9
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/pr81574.C
@@ -0,0 +1,13 @@
+// { dg-do compile { target c++14 } }
+// PR c++/81574 references to functions are captured by reference.
+
+// 8.1.5.2/10
+// For each entity captured by copy, ... an lvalue reference to the
+// referenced function type if the entity is a reference to a function
+
+void f (void (&b)())
+{
+  [=] {  b; } ();
+  [=, b(f)] { b; } ();
+  [=, b(b)] { b; } ();
+}