[Bug c++/111607] False positive -Wdangling-reference

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111607

Marek Polacek <mpolacek at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |mpolacek at gcc dot gnu.org
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=113256
   Last reconfirmed|                            |2024-01-18
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |ASSIGNED

--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Thanks for the report.  I suppose we should not warn when the argument is a
lambda type.  This might also fix bug 113256.

--- a/gcc/cp/call.cc
+++ b/gcc/cp/call.cc
@@ -14123,7 +14123,8 @@ do_warn_dangling_reference (tree expr, bool arg_p)
       tree e = expr;
       while (handled_component_p (e))
    e = TREE_OPERAND (e, 0);
-      if (!reference_like_class_p (TREE_TYPE (e)))
+      if (!reference_like_class_p (TREE_TYPE (e))
+     && !LAMBDA_TYPE_P (TREE_TYPE (e)))
    return expr;
     }

@@ -14180,10 +14181,10 @@ do_warn_dangling_reference (tree expr, bool arg_p)
           initializing this reference parameter.  */
        if (do_warn_dangling_reference (arg, /*arg_p=*/true))
          return expr;
-     /* Don't warn about member function like:
+     /* Don't warn about member functions like:
          std::any a(...);
          S& s = a.emplace<S>({0}, 0);
-        which constructs a new object and returns a reference to it, but
+        which construct a new object and return a reference to it, but
         we still want to detect:
           struct S { const S& self () { return *this; } };
           const S& s = S().self();