There were two issues in this PR:
1) We were crashing in is_really_empty_class because we say that the
internal RTTI types are classes, but never gave them TYPE_BINFO.
2) We were allowing the cast to a different pointer type because STRIP_NOPS
in cxx_fold_indirect_ref ignored REINTERPRET_CAST_P.
Tested x86_64-pc-linux-gnu, applying to trunk.
* rtti.c (get_tinfo_desc): Call xref_basetypes.
* constexpr.c (cxx_fold_indirect_ref): Don't strip
REINTERPRET_CAST_P.
---
gcc/cp/constexpr.c | 11 +++++++++-
gcc/cp/rtti.c | 1 +
.../g++.dg/cpp0x/constexpr-reinterpret2.C | 21 +++++++++++++++++++
gcc/testsuite/g++.dg/rtti/typeid13.C | 11 ++++++++++
4 files changed, 43 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/constexpr-reinterpret2.C
create mode 100644 gcc/testsuite/g++.dg/rtti/typeid13.C
diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
index 3a9fb566a52..bb126a9c006 100644
--- a/gcc/cp/constexpr.c
+++ b/gcc/cp/constexpr.c
@@ -4023,7 +4023,16 @@ cxx_fold_indirect_ref (location_t loc, tree type, tree
op0, bool *empty_base)
tree subtype;
poly_uint64 const_op01;
- STRIP_NOPS (sub);
+ /* STRIP_NOPS, but stop if REINTERPRET_CAST_P. */
+ while (CONVERT_EXPR_P (sub) || TREE_CODE (sub) == NON_LVALUE_EXPR
+ || TREE_CODE (sub) == VIEW_CONVERT_EXPR)
+ {
+ if (TREE_CODE (sub) == NOP_EXPR
+ && REINTERPRET_CAST_P (sub))
+ return NULL_TREE;
+ sub = TREE_OPERAND (sub, 0);
+ }
+
subtype = TREE_TYPE (sub);
if (!INDIRECT_TYPE_P (subtype))
return NULL_TREE;
diff --git a/gcc/cp/rtti.c b/gcc/cp/rtti.c
index 2fc52f07980..36c1b4ed7bc 100644
--- a/gcc/cp/rtti.c
+++ b/gcc/cp/rtti.c
@@ -1472,6 +1472,7 @@ get_tinfo_desc (unsigned ix)
/* Pass the fields chained in reverse. */
finish_builtin_struct (pseudo_type, pseudo_name, fields, NULL_TREE);
CLASSTYPE_AS_BASE (pseudo_type) = pseudo_type;
+ xref_basetypes (pseudo_type, /*bases=*/NULL_TREE);
res->type = cp_build_qualified_type (pseudo_type, TYPE_QUAL_CONST);
res->name = get_identifier (real_name);
diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-reinterpret2.C
b/gcc/testsuite/g++.dg/cpp0x/constexpr-reinterpret2.C
new file mode 100644
index 00000000000..1bc2a8f3012
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-reinterpret2.C
@@ -0,0 +1,21 @@
+// { dg-do compile { target c++11 } }
+
+struct S { void *p; };
+struct T { S s; };
+constexpr S s = { nullptr };
+constexpr T t = { { nullptr } };
+
+constexpr void *
+foo ()
+{
+ return ((void **) &t)[0]; // { dg-error "reinterpret_cast" }
+}
+
+constexpr void *
+bar ()
+{
+ return ((void **) &s)[0]; // { dg-error "reinterpret_cast" }
+}
+
+constexpr auto x = foo ();
+constexpr auto y = bar ();
diff --git a/gcc/testsuite/g++.dg/rtti/typeid13.C
b/gcc/testsuite/g++.dg/rtti/typeid13.C
new file mode 100644
index 00000000000..d42005ed0d6
--- /dev/null
+++ b/gcc/testsuite/g++.dg/rtti/typeid13.C
@@ -0,0 +1,11 @@
+// PR c++/92009
+
+namespace std {
+ class type_info {};
+}
+
+bool
+a2 ()
+{
+ return ((void **) &typeid (int))[0];
+}
base-commit: 03e87724864a17e22c9b692cc0caa014e9dba6b1
--
2.18.1
