diff options
author | Jonathan Wakely <jwakely@redhat.com> | 2024-03-27 21:51:13 +0000 |
---|---|---|
committer | Jonathan Wakely <jwakely@redhat.com> | 2024-04-03 11:45:35 +0100 |
commit | 7f65d8267fbfd19cf21a3dc71d27e989e75044a3 (patch) | |
tree | 9330cb9c83b0b7b7f77bc2316bc5ced9b894630c /libstdc++-v3 | |
parent | b2460d621efe740bd95ad41afef6d806ec1bd9c7 (diff) | |
download | gcc-7f65d8267fbfd19cf21a3dc71d27e989e75044a3.zip gcc-7f65d8267fbfd19cf21a3dc71d27e989e75044a3.tar.gz gcc-7f65d8267fbfd19cf21a3dc71d27e989e75044a3.tar.bz2 |
libstdc++: Reverse arguments in constraint for std::optional's <=> [PR104606]
This is a workaround for a possible compiler bug that causes constraint
recursion in the operator<=>(const optional<T>&, const U&) overload.
libstdc++-v3/ChangeLog:
PR libstdc++/104606
* include/std/optional (operator<=>(const optional<T>&, const U&)):
Reverse order of three_way_comparable_with template arguments.
* testsuite/20_util/optional/relops/104606.cc: New test.
Diffstat (limited to 'libstdc++-v3')
-rw-r--r-- | libstdc++-v3/include/std/optional | 2 | ||||
-rw-r--r-- | libstdc++-v3/testsuite/20_util/optional/relops/104606.cc | 18 |
2 files changed, 19 insertions, 1 deletions
diff --git a/libstdc++-v3/include/std/optional b/libstdc++-v3/include/std/optional index 1e88e8b..3507c36 100644 --- a/libstdc++-v3/include/std/optional +++ b/libstdc++-v3/include/std/optional @@ -1430,7 +1430,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION #ifdef __cpp_lib_three_way_comparison template<typename _Tp, typename _Up> requires (!__is_optional_v<_Up>) - && three_way_comparable_with<_Tp, _Up> + && three_way_comparable_with<_Up, _Tp> constexpr compare_three_way_result_t<_Tp, _Up> operator<=>(const optional<_Tp>& __x, const _Up& __v) { return bool(__x) ? *__x <=> __v : strong_ordering::less; } diff --git a/libstdc++-v3/testsuite/20_util/optional/relops/104606.cc b/libstdc++-v3/testsuite/20_util/optional/relops/104606.cc new file mode 100644 index 0000000..2b8df24 --- /dev/null +++ b/libstdc++-v3/testsuite/20_util/optional/relops/104606.cc @@ -0,0 +1,18 @@ +// { dg-do compile { target c++17 } } + +// Bug 104606 comparison operator resolution with std::optional and -std=c++20 + +#include <optional> +#include <variant> +#include <vector> + +struct Value : std::variant<std::vector<Value>> { }; + +struct Comparator { + template <typename T> bool operator<=(const T &) { return true; } +}; + +std::optional<Value> o; +Comparator c; + +auto x = c <= o; |