The patch that I merged via r15-4282-g60163c85730e6b breaks the build
for the rust front-end because it does not work well when virtual
inheritance is in play.
The problem is that in such a case, an overrider and its overridden base
method might have a different DECL_VINDEX, and the derived method would
be incorrectly considered as hiding the base one.
This patch fixes this by not comparing the DECL_VINDEX anymore, but
rather going back to comparing the signatures, only after having
excluded conversion operators to different types.
I'm currently running the testsuite on x86_64-pc-linux-gnu, and already
verified that the rust front-end builds again with the patch applied.
OK if the testsuite run finishes successfully?
PR c++/117114
gcc/cp/ChangeLog:
* class.cc (warn_hidden): Don't compare DECL_VINDEX but
signatures, after having excluded operators to different types.
gcc/testsuite/ChangeLog:
* g++.dg/warn/Woverloaded-virt10.C: New test.
---
gcc/cp/class.cc | 20 +++++++++----------
.../g++.dg/warn/Woverloaded-virt10.C | 7 +++++++
2 files changed, 17 insertions(+), 10 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/warn/Woverloaded-virt10.C
diff --git a/gcc/cp/class.cc b/gcc/cp/class.cc
index f754886a60a..fce71483ccc 100644
--- a/gcc/cp/class.cc
+++ b/gcc/cp/class.cc
@@ -3279,25 +3279,25 @@ warn_hidden (tree t)
{
num_fns++;
tree fndecl_vindex = DECL_VINDEX (fndecl);
- /* If the method from the base class has the same DECL_VINDEX
- as the method from the derived, it has been overridden.
+ /* If the methods from the base and derived classes have the
+ same signature and they are not conversion operators to
+ different types, then the base method has been overriden.
Note that we can't move on after finding one match: fndecl
might override multiple base fns. */
for (size_t k = 0; k < base_fndecls.length (); k++)
{
if (!base_fndecls[k] || !DECL_VINDEX (base_fndecls[k]))
continue;
- tree base_fndecl_vindex = DECL_VINDEX (base_fndecls[k]);
- if (fndecl_vindex
- && !tree_int_cst_compare (fndecl_vindex,
- base_fndecl_vindex))
- overriden_base_fndecls.add (base_fndecls[k]);
- else if (IDENTIFIER_CONV_OP_P (name)
- && (DECL_NAME (fndecl)
- != DECL_NAME (base_fndecls[k])))
+ if (IDENTIFIER_CONV_OP_P (name)
+ && (DECL_NAME (fndecl)
+ != DECL_NAME (base_fndecls[k])))
/* If base_fndecl[k] and fndecl are conversion operators
to different types, they're unrelated. */
;
+ else if (same_signature_p (fndecl, base_fndecls[k]))
+ /* If fndecl has the same signature as base_fndecl[k], it
+ overrides it. */
+ overriden_base_fndecls.add (base_fndecls[k]);
else
hidden_base_fndecls.put (base_fndecls[k], fndecl);
}
diff --git a/gcc/testsuite/g++.dg/warn/Woverloaded-virt10.C
b/gcc/testsuite/g++.dg/warn/Woverloaded-virt10.C
new file mode 100644
index 00000000000..5e669360ec9
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Woverloaded-virt10.C
@@ -0,0 +1,7 @@
+// PR c++/117114
+// { dg-do compile { target c++11 } }
+// { dg-additional-options -Wall }
+
+struct Troops { virtual ~Troops(); };
+struct Control { virtual int GetControl() const = 0; };
+struct Army : Troops, Control { int GetControl() const override; };
--
2.44.0
