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| author | gnaggnoyil <gnaggnoyil@gmail.com> | 2023-08-12 16:16:52 +0800 |
|---|---|---|
| committer | Jason Merrill <jason@redhat.com> | 2023-08-14 13:34:42 -0400 |
| commit | 1a43af04dd62b80f45700f94ed241347263ed773 (patch) | |
| tree | 9fadb25f3c3c69f55990a3d9802b3c6a6a2984a4 /gcc | |
| parent | cc56607f21f77d4e9c8146cd1b0400fddea589c6 (diff) | |
| download | gcc-1a43af04dd62b80f45700f94ed241347263ed773.zip gcc-1a43af04dd62b80f45700f94ed241347263ed773.tar.gz gcc-1a43af04dd62b80f45700f94ed241347263ed773.tar.bz2 | |
c++: follow DR 2386 and update implementation of get_tuple_size [PR110216]
DR 2386 updated the tuple_size requirements for structured binding and
it now requires tuple_size to be considered only if
std::tuple_size<TYPE> names a complete class type with member value. GCC
before this patch does not follow the updated requrements, and this
patch is intended to implement it.
(jason) Accepting pseudonym sign-off because a change this small is not
legally significant for copyright.
DR 2386
PR c++/110216
gcc/cp/ChangeLog:
* decl.cc (get_tuple_size): Update implementation for DR 2386.
gcc/testsuite/ChangeLog:
* g++.dg/cpp1z/decomp10.C: Update expected error for DR 2386.
* g++.dg/cpp1z/pr110216.C: New test.
Signed-off-by: gnaggnoyil <gnaggnoyil@gmail.com>
Reviewed-by: Jason Merrill <jason@redhat.com>
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/cp/decl.cc | 6 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/cpp1z/decomp10.C | 2 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/cpp1z/pr110216.C | 21 |
3 files changed, 27 insertions, 2 deletions
diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc index 126c581..62c34bf9 100644 --- a/gcc/cp/decl.cc +++ b/gcc/cp/decl.cc @@ -8932,10 +8932,14 @@ get_tuple_size (tree type) /*context*/std_node, /*entering_scope*/false, tf_none); inst = complete_type (inst); - if (inst == error_mark_node || !COMPLETE_TYPE_P (inst)) + if (inst == error_mark_node + || !COMPLETE_TYPE_P (inst) + || !CLASS_TYPE_P (type)) return NULL_TREE; tree val = lookup_qualified_name (inst, value_identifier, LOOK_want::NORMAL, /*complain*/false); + if (val == error_mark_node) + return NULL_TREE; if (VAR_P (val) || TREE_CODE (val) == CONST_DECL) val = maybe_constant_value (val); if (TREE_CODE (val) == INTEGER_CST) diff --git a/gcc/testsuite/g++.dg/cpp1z/decomp10.C b/gcc/testsuite/g++.dg/cpp1z/decomp10.C index f0723f8..af83a79 100644 --- a/gcc/testsuite/g++.dg/cpp1z/decomp10.C +++ b/gcc/testsuite/g++.dg/cpp1z/decomp10.C @@ -7,7 +7,7 @@ namespace std { struct A1 { int i,j; } a1; template<> struct std::tuple_size<A1> { }; -void f1() { auto [ x ] = a1; } // { dg-error "is not an integral constant expression" } +void f1() { auto [ x ] = a1; } // { dg-error "only 1 name provided" } struct A2 { int i,j; } a2; template<> struct std::tuple_size<A2> { enum { value = 5 }; }; diff --git a/gcc/testsuite/g++.dg/cpp1z/pr110216.C b/gcc/testsuite/g++.dg/cpp1z/pr110216.C new file mode 100644 index 0000000..be4fd5f --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp1z/pr110216.C @@ -0,0 +1,21 @@ +// DR 2386 +// PR c++/110216 +// { dg-do compile { target c++17 } } + + +namespace std{ + template <typename T> struct tuple_size; +} + +struct A { + int x = 0; +}; + +template <> struct std::tuple_size <::A> {}; + +auto [x] = A{}; + +int +main () +{ +} |