On 4/25/20 6:54 PM, Marek Polacek wrote:
On Sat, Apr 25, 2020 at 12:17:18AM -0400, Jason Merrill via Gcc-patches wrote:
P2085 clarified that a defaulted comparison operator must be the first
declaration of the function. Rejecting that avoids the ICE trying to
compare the noexcept-specifications.
Tested x86_64-pc-linux-gnu, applying to trunk.
gcc/cp/ChangeLog
2020-04-24 Jason Merrill <ja...@redhat.com>
PR c++/94583
* decl.c (redeclaration_error_message): Reject defaulted comparison
operator that has been previously declared.
---
gcc/cp/decl.c | 8 ++++++++
gcc/testsuite/g++.dg/cpp2a/spaceship-synth6.C | 11 +++++++++++
2 files changed, 19 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/cpp2a/spaceship-synth6.C
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index c8c2f080763..31b5884ca3a 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -2972,6 +2972,14 @@ redeclaration_error_message (tree newdecl, tree olddecl)
}
}
+ /* [class.compare.default]: A definition of a comparison operator as
+ defaulted that appears in a class shall be the first declaration of
+ that function. */
+ special_function_kind sfk = special_function_p (olddecl);
+ if (sfk == sfk_comparison && DECL_DEFAULTED_FN (newdecl))
+ return G_("comparison operator %q+D defaulted after "
+ "its first declaration");
+
This one still ICEs:
namespace std { struct strong_ordering { }; }
struct Q {
friend std::strong_ordering operator<=>(const Q&, const Q&) = default;
};
bool operator==(const Q&, const Q&) noexcept;
Fixed, thanks.
Jason
