re PR c++/92666 (bogus -Wunused-but-set-variable in gcov.c with -Wno-restrict)

	PR c++/92666
	* call.c (convert_arg_to_ellipsis): For floating point or
	decltype(nullptr) arguments call mark_rvalue_use.

	* g++.dg/warn/Wunused-var-36.C: New test.

From-SVN: r279681

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index c6858f9..5a9a648 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 2019-12-20  Jakub Jelinek  <jakub@redhat.com>
 
+       PR c++/92666
+       * call.c (convert_arg_to_ellipsis): For floating point or
+       decltype(nullptr) arguments call mark_rvalue_use.
+
        PR c++/92992
        * call.c (convert_arg_to_ellipsis): For decltype(nullptr) arguments
        that have side-effects use cp_build_compound_expr.

diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index aeddf30..1abe1a7 100644 (file)
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -7819,10 +7819,12 @@ convert_arg_to_ellipsis (tree arg, tsubst_flags_t complain)
                    "implicit conversion from %qH to %qI when passing "
                    "argument to function",
                    arg_type, double_type_node);
+      arg = mark_rvalue_use (arg);
       arg = convert_to_real_nofold (double_type_node, arg);
     }
   else if (NULLPTR_TYPE_P (arg_type))
     {
+      arg = mark_rvalue_use (arg);
       if (TREE_SIDE_EFFECTS (arg))
        arg = cp_build_compound_expr (arg, null_pointer_node, complain);
       else

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d2e1464..dd9e529 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2019-12-20  Jakub Jelinek  <jakub@redhat.com>
 
+       PR c++/92666
+       * g++.dg/warn/Wunused-var-36.C: New test.
+
        PR c++/92992
        * g++.dg/cpp0x/nullptr45.C: New test.
 

diff --git a/gcc/testsuite/g++.dg/warn/Wunused-var-36.C b/gcc/testsuite/g++.dg/warn/Wunused-var-36.C
new file mode 100644 (file)
index 0000000..de338f8
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wunused-var-36.C
@@ -0,0 +1,25 @@
+// PR c++/92666
+// { dg-do compile }
+// { dg-options "-Wunused-but-set-variable" }
+
+int bar (int, ...);
+#if __cplusplus >= 201103L
+enum class E : int { F = 0, G = 1 };
+#endif
+struct S { int s; };
+
+void
+foo ()
+{
+  float r = 1.0f;                      // { dg-bogus "set but not used" }
+  int i = 2;                           // { dg-bogus "set but not used" }
+#if __cplusplus >= 201103L
+  decltype(nullptr) n = nullptr;       // { dg-bogus "set but not used" }
+  E e = E::F;                          // { dg-bogus "set but not used" }
+#else
+  void *n = (void *) 0;
+  int e = 4;
+#endif
+  S s = { 3 };                         // { dg-bogus "set but not used" }
+  bar (0, r, i, n, e, s);
+}