The code for adding a conversion op to a lambda closure was checking
whether there were any captures before we had gotten around to setting
up the capture list. Fixed by instantiating it a bit sooner.
Tested x86_64-pc-linux-gnu, applying to trunk.
commit 75607bcd47d0be87cfaca0ebf625986ecde78a7d
Author: Jason Merrill <ja...@redhat.com>
Date: Fri Feb 15 12:04:34 2013 -0500
PR c++/56447
PR c++/55532
* pt.c (instantiate_class_template_1): Instantiate lambda capture
list here.
(tsubst_copy_and_build): Not here.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 6264add..126e110 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -8991,12 +8991,26 @@ instantiate_class_template_1 (tree type)
}
}
- if (CLASSTYPE_LAMBDA_EXPR (type))
+ if (tree expr = CLASSTYPE_LAMBDA_EXPR (type))
{
tree decl = lambda_function (type);
if (decl)
{
instantiate_decl (decl, false, false);
+
+ /* We need to instantiate the capture list from the template
+ after we've instantiated the closure members, but before we
+ consider adding the conversion op. Also keep any captures
+ that may have been added during instantiation of the op(). */
+ tree tmpl_expr = CLASSTYPE_LAMBDA_EXPR (pattern);
+ tree tmpl_cap
+ = tsubst_copy_and_build (LAMBDA_EXPR_CAPTURE_LIST (tmpl_expr),
+ args, tf_warning_or_error, NULL_TREE,
+ false, false);
+
+ LAMBDA_EXPR_CAPTURE_LIST (expr)
+ = chainon (tmpl_cap, nreverse (LAMBDA_EXPR_CAPTURE_LIST (expr)));
+
maybe_add_lambda_conv_op (type);
}
else
@@ -14470,12 +14484,6 @@ tsubst_copy_and_build (tree t,
declaration of the op() for later calls to lambda_function. */
complete_type (type);
- /* The capture list refers to closure members, so this needs to
- wait until after we finish instantiating the type. Also keep
- any captures that may have been added during instantiation. */
- LAMBDA_EXPR_CAPTURE_LIST (r)
- = chainon (RECUR (LAMBDA_EXPR_CAPTURE_LIST (t)),
- LAMBDA_EXPR_CAPTURE_LIST (r));
LAMBDA_EXPR_THIS_CAPTURE (r) = NULL_TREE;
RETURN (build_lambda_object (r));
diff --git a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-conv8.C b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-conv8.C
new file mode 100644
index 0000000..abe272a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-conv8.C
@@ -0,0 +1,15 @@
+// PR c++/56447
+// { dg-do compile { target c++11 } }
+
+template <class T>
+void f()
+{
+ int i;
+ // This lambda should not have a conversion op, since it captures i
+ int (*p)() = [=]{ return i; }; // { dg-error "cannot convert" }
+}
+
+int main()
+{
+ f<int>();
+}
diff --git a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-mutable2.C b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-mutable2.C
new file mode 100644
index 0000000..c54ff5c
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-mutable2.C
@@ -0,0 +1,23 @@
+// PR c++/55532
+// { dg-do compile { target c++11 } }
+
+struct Foo {
+ void doit() {
+ }
+};
+
+template<typename T>
+void oops(Foo &foo, const T &) {
+ auto fun = [&] () mutable {
+ foo.doit();
+ };
+ auto fun2 = [=]() {
+ fun(); // { dg-error "" }
+ };
+ fun2();
+}
+
+int main() {
+ Foo foo;
+ oops(foo, 1);
+}
