This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
[PATCH] [PR87012] canonicalize ref type for tmpl arg
- From: Alexandre Oliva <aoliva at redhat dot com>
- To: gcc-patches at gcc dot gnu dot org
- Cc: jason at redhat dot com, nathan at acm dot org
- Date: Fri, 16 Nov 2018 20:32:38 -0200
- Subject: [PATCH] [PR87012] canonicalize ref type for tmpl arg
When binding an object to a template parameter of reference type, we
take the address of the object and dereference that address. The type
of the address may still carry (template) typedefs, but
verify_unstripped_args_1 rejects such typedefs other than in the top
level of template arguments.
We might special-case INDIRECT_REFs, but I suppose we're better off
canonicalizing the desired type for the address before converting to
it.
Regstrapped on i686- and x86_64-linux-gnu. Ok to install?
for gcc/cp/ChangeLog
PR c++/87012
* pt.c (canonicalize_type_argument): Declare earlier.
(convert_nontype_argument): Call it on addr expr.
for gcc/testsuite/ChangeLog
PR c++/87012
* g++.dg/cpp0x/pr87012.C: New.
---
gcc/cp/pt.c | 4 ++++
gcc/testsuite/g++.dg/cpp0x/pr87012.C | 11 +++++++++++
2 files changed, 15 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/pr87012.C
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index b58ec06a09e5..83d0a74b209f 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -227,6 +227,8 @@ static tree make_argument_pack (tree);
static void register_parameter_specializations (tree, tree);
static tree enclosing_instantiation_of (tree tctx);
+static tree canonicalize_type_argument (tree arg, tsubst_flags_t complain);
+
/* Make the current scope suitable for access checking when we are
processing T. T can be FUNCTION_DECL for instantiated function
template, VAR_DECL for static member variable, or TYPE_DECL for
@@ -7016,6 +7018,8 @@ convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
return NULL_TREE;
}
+ type = canonicalize_type_argument (type, complain);
+
if (!same_type_p (type, TREE_TYPE (expr)))
expr = build_nop (type, expr);
}
diff --git a/gcc/testsuite/g++.dg/cpp0x/pr87012.C b/gcc/testsuite/g++.dg/cpp0x/pr87012.C
new file mode 100644
index 000000000000..fd3eea47c390
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/pr87012.C
@@ -0,0 +1,11 @@
+// { dg-do compile { target c++11 } }
+
+template<class T>
+using ref = T&;
+
+int x;
+
+template<template<class> class T, T<int>>
+struct X { };
+
+struct Y : X<ref, x> { };
--
Alexandre Oliva, freedom fighter https://FSFLA.org/blogs/lxo
Be the change, be Free! FSF Latin America board member
GNU Toolchain Engineer Free Software Evangelist
Hay que enGNUrecerse, pero sin perder la terGNUra jamás-GNUChe