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

[Jason Merrill via Gcc-patches]

On 4/7/20 3:14 PM, Marek Polacek wrote:

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.

Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?


OK.


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.
---
  gcc/cp/method.c | 11 +++
  gcc/testsuite/g++.dg/cpp2a/spaceship-err4.C |  7 +++
  2 files changed, 18 insertions(+)
  create mode 100644 gcc/testsuite/g++.dg/cpp2a/spaceship-err4.C

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/g++.dg/cpp2a/spaceship-err4.C 
b/gcc/testsuite/g++.dg/cpp2a/spaceship-err4.C
new file mode 100644
index 000..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" }

base-commit: 3d947f1f27188e3a61ba7f42399b1c348469fe13

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

[Marek Polacek via Gcc-patches]

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.

Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?

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.
---
 gcc/cp/method.c | 11 +++
 gcc/testsuite/g++.dg/cpp2a/spaceship-err4.C |  7 +++
 2 files changed, 18 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/cpp2a/spaceship-err4.C

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/g++.dg/cpp2a/spaceship-err4.C 
b/gcc/testsuite/g++.dg/cpp2a/spaceship-err4.C
new file mode 100644
index 000..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" }

base-commit: 3d947f1f27188e3a61ba7f42399b1c348469fe13
-- 
Marek Polacek • Red Hat, Inc. • 300 A St, Boston, MA