re PR c++/92695 (P1064R0 - virtual constexpr fails if object taken from array)

	PR c++/92695
	* decl2.c (mark_used): Don't call note_vague_linkage_fn for pure
	virtual functions, even if they are declared inline.

	* g++.dg/warn/inline3.C: New test.

From-SVN: r278802

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index ec37f5ec4f2477e9c1ddee22c460e23bbbe235dd..8b71f02cf10c89830e366f47656007cc50e62661 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2019-11-28  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c++/92695
+       * decl2.c (mark_used): Don't call note_vague_linkage_fn for pure
+       virtual functions, even if they are declared inline.
+
 2019-11-16  Jason Merrill  <jason@redhat.com>
 
        Implement P1814R0, CTAD for alias templates.

diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c
index f164494afdc6c19b523f6e54e45a08bc5d9923fd..46cc58265a64fbab9133bf502869d015c07f7ab8 100644 (file)
--- a/gcc/cp/decl2.c
+++ b/gcc/cp/decl2.c
@@ -5596,8 +5596,11 @@ mark_used (tree decl, tsubst_flags_t complain)
        vec_safe_push (no_linkage_decls, decl);
     }
 
-  if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl)
-      && !DECL_INITIAL (decl) && !DECL_ARTIFICIAL (decl))
+  if (TREE_CODE (decl) == FUNCTION_DECL
+      && DECL_DECLARED_INLINE_P (decl)
+      && !DECL_INITIAL (decl)
+      && !DECL_ARTIFICIAL (decl)
+      && !DECL_PURE_VIRTUAL_P (decl))
     /* Remember it, so we can check it was defined.  */
     note_vague_linkage_fn (decl);
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 4f97f4cc58c57fde608d312e08f79e365f6bafb1..0bcac2a12b54fc9ba6b27dc506bf7be1411a11ea 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-11-28  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c++/92695
+       * g++.dg/warn/inline3.C: New test.
+
 2019-11-27  Jakub Jelinek  <jakub@redhat.com>
 
        PR rtl-optimization/92510

diff --git a/gcc/testsuite/g++.dg/warn/inline3.C b/gcc/testsuite/g++.dg/warn/inline3.C
new file mode 100644 (file)
index 0000000..0d4dc8f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/inline3.C
@@ -0,0 +1,20 @@
+struct S {
+  inline virtual void foo () = 0;      // { dg-bogus "used but never defined" }
+#if __cplusplus > 201703L
+  constexpr virtual void bar () = 0;   // { dg-bogus "used but never defined" "" { target c++2a } }
+#else
+  inline virtual void bar () = 0;      // { dg-bogus "used but never defined" "" { target c++17_down }  }
+#endif
+  S () {}
+};
+struct T : public S {
+  inline virtual void foo () {}
+#if __cplusplus > 201703L
+  constexpr virtual void bar () {}
+#else
+  inline virtual void bar () {}
+#endif
+  T () {}
+};
+T t;
+void foo (S *s) { s->foo (); s->bar (); }