http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57831
Bug ID: 57831
Summary: pointer to member function inaccessible through using
statement (or ICE)
Product: gcc
Version: 4.9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: t-gcc-bugzilla at snowelm dot com
g++ 4.8.1 rejects the following code saying "B<T>::base::f is inaccessible".
I believe the code is valid (and compiled without error by Clang).
Moreover, when I use the trunk head g++, it crashes with ICE.
----------------------------
struct A {
void f();
};
template <class T> struct B : T {
typedef T base;
using base::f; // If I write "using B<T>::f" it's ok
void g( ) {
B<T>::f(); // This is OK as expected
(this->*&T::f)(); // This is also OK
(this->*&B<T>::f)(); // This causes error
}
};
template struct B< A >;
----------------------------
It is strange to see "inaccessible" error, since everything in the code is
public.
The oldest g++ in my environment (g++ 4.4) also rejects the code.
Coupiler output for g++ 4.8.1 and g++ trunk are attached below
Possibly related to PR 57658 or PR 53549.
------------------------------
$ g++-4.8 -v
Using built-in specs.
COLLECT_GCC=g++-4.8
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-unknown-linux-gnu/4.8.1/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../configure --prefix=/usr/local --program-suffix=-4.8
--enable-languages=c,c++,lto
Thread model: posix
gcc version 4.8.1 (GCC)
$ g++-4.8 hoge.ii
hoge.ii: In instantiation of 'void B<T>::g() [with T = A]':
hoge.ii:13:17: required from here
hoge.ii:6:14: error: 'using B<T>::base::f' is inaccessible
using base::f;
^
hoge.ii:10:13: error: within this context
(this->*&B<T>::f)();
^
hoge.ii:10:10: error: pointer to member type 'B<T>::base' incompatible with
object type 'B<A>'
(this->*&B<T>::f)();
------------------------------
$ g++-4.9 -v
Using built-in specs.
COLLECT_GCC=g++-4.9
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-unknown-linux-gnu/4.9.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../configure --prefix=/usr/local --program-suffix=-4.9
--enable-languages=c,c++,lto
Thread model: posix
gcc version 4.9.0 20130705 (experimental) (GCC)
$ g++-4.9 hoge.ii
hoge.ii: In instantiation of 'void B<T>::g() [with T = A]':
hoge.ii:13:17: required from here
hoge.ii:10:13: internal compiler error: in tsubst_copy, at cp/pt.c:12616
(this->*&B<T>::f)();
^
0x59f08b tsubst_copy
../../gcc/cp/pt.c:12616
0x5b4bb9 tsubst_qualified_id
../../gcc/cp/pt.c:12013
0x58062b tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
../../gcc/cp/pt.c:13684
0x57f906 tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
../../gcc/cp/pt.c:13738
0x57e66b tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
../../gcc/cp/pt.c:14013
0x5874f2 tsubst_expr
../../gcc/cp/pt.c:13429
0x587a4f tsubst_expr
../../gcc/cp/pt.c:12908
0x586f93 tsubst_expr
../../gcc/cp/pt.c:12894
0x587d64 tsubst_expr
../../gcc/cp/pt.c:13084
0x5858bc instantiate_decl(tree_node*, int, bool)
../../gcc/cp/pt.c:19157
0x5c14ff instantiate_pending_templates(int)
../../gcc/cp/pt.c:19256
0x5fd809 cp_write_global_declarations()
../../gcc/cp/decl2.c:4063
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
------------------------------
