From: Marek Polacek <polacek@redhat.com>
Date: Tue, 7 Apr 2020 18:24:52 +0000 (-0400)
Subject: c++: ICE with defaulted comparison operator [PR94478]
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=a6479aa4c0532ee9ad1f098b4e82de9dc684e036;p=gcc.git

c++: ICE with defaulted comparison operator [PR94478]

Here we ICE because early_check_defaulted_comparison passed a null
ctx to same_type_p.  The attached test is ill-formed according to
[class.compare.default]/1, so fixed by detecting this case early.

	PR c++/94478 - ICE with defaulted comparison operator
	* method.c (early_check_defaulted_comparison): Give an error when the
	context is null.

	* g++.dg/cpp2a/spaceship-err4.C: New test.
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 561eb4e76f4..3fb9100e023 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2020-04-08  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/94478 - ICE with defaulted comparison operator
+	* method.c (early_check_defaulted_comparison): Give an error when the
+	context is null.
+
 2020-04-08  Tobias Burnus  <tobias@codesourcery.com>
 
 	PR middle-end/94120
diff --git a/gcc/cp/method.c b/gcc/cp/method.c
index 41b9ff86bdd..9a21bfc1f66 100644
--- a/gcc/cp/method.c
+++ b/gcc/cp/method.c
@@ -1102,6 +1102,17 @@ early_check_defaulted_comparison (tree fn)
       return false;
     }
 
+  if (!ctx)
+    {
+      if (DECL_OVERLOADED_OPERATOR_IS (fn, SPACESHIP_EXPR))
+	error_at (loc, "three-way comparison operator can only be defaulted "
+		  "in a class definition");
+      else
+	error_at (loc, "equality comparison operator can only be defaulted "
+		  "in a class definition");
+      return false;
+    }
+
   if (!DECL_OVERLOADED_OPERATOR_IS (fn, SPACESHIP_EXPR)
       && !same_type_p (TREE_TYPE (TREE_TYPE (fn)), boolean_type_node))
     {
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 3913d212c69..278330f528f 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2020-04-08  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/94478 - ICE with defaulted comparison operator
+	* g++.dg/cpp2a/spaceship-err4.C: New test.
+
 2020-04-08  Alexandre Oliva <oliva@adacore.com>
 
 	* gcc.target/arm/polytypes.c: Add quotes around
diff --git a/gcc/testsuite/g++.dg/cpp2a/spaceship-err4.C b/gcc/testsuite/g++.dg/cpp2a/spaceship-err4.C
new file mode 100644
index 00000000000..00f90ced255
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/spaceship-err4.C
@@ -0,0 +1,7 @@
+// PR c++/94478 - ICE with defaulted comparison operator.
+// { dg-do compile { target c++2a } }
+
+struct B {};
+bool operator!=(const B&, const B&) = default; // { dg-error "equality comparison operator can only be defaulted in a class definition" }
+bool operator==(const B&, const B&) = default; // { dg-error "equality comparison operator can only be defaulted in a class definition" }
+bool operator<=>(const B&, const B&) = default; // { dg-error "three-way comparison operator can only be defaulted in a class definition" }