diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/cp/decl.c | 6 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/cpp1z/decomp55.C | 19 |
2 files changed, 25 insertions, 0 deletions
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c index 8e8f37d..b1d8e44 100644 --- a/gcc/cp/decl.c +++ b/gcc/cp/decl.c @@ -8629,6 +8629,12 @@ cp_finish_decomp (tree decl, tree first, unsigned int count) : get_tuple_element_type (type, i)); input_location = sloc; + if (VOID_TYPE_P (eltype)) + { + error ("%<std::tuple_element<%u, %T>::type%> is %<void%>", + i, type); + eltype = error_mark_node; + } if (init == error_mark_node || eltype == error_mark_node) { inform (dloc, "in initialization of structured binding " diff --git a/gcc/testsuite/g++.dg/cpp1z/decomp55.C b/gcc/testsuite/g++.dg/cpp1z/decomp55.C new file mode 100644 index 0000000..bb4bf75 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp1z/decomp55.C @@ -0,0 +1,19 @@ +// PR c++/99650 +// { dg-do compile { target c++17 } } + +namespace std { + template<typename T> struct tuple_size; + template<int, typename> struct tuple_element; +} + +struct A { + int i; + template <int I> void get() { } +}; + +template<> struct std::tuple_size<A> { static const int value = 2; }; +template<int I> struct std::tuple_element<I,A> { using type = void; }; + +A a = { 42 }; +auto [ x, y ] = a; // { dg-error ".std::tuple_element<0, A>::type. is .void." } +// { dg-message "in initialization of structured binding variable 'x'" "" { target *-*-* } .-1 } |