PR c++/60531 - Wrong error about unresolved overloaded function

For PR60531, GCC wrongly rejects function templates with explicitly
specified template arguments as overloaded. They are resolved by
resolve_nondeduced_context, which is normally called by
cp_default_conversion through decay_conversion, but the latter have
extra effects making them unusable here. Calling the former directly
does work.

	* typeck.c (cp_build_binary_op): See if overload can be resolved.
	(cp_build_unary_op): Ditto.

	* g++.dg/template/operator15.C: New test.

From-SVN: r271910

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index efa79f3..21b82df 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2019-06-04  Harald van Dijk  <harald@gigawatt.nl>
+
+       PR c++/60531 - Wrong error about unresolved overloaded function
+       * typeck.c (cp_build_binary_op): See if overload can be resolved.
+       (cp_build_unary_op): Ditto.
+
 2019-06-04  Jason Merrill  <jason@redhat.com>
 
        Reduce accumulated garbage in constexpr evaluation.

diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 7289f2c..b9fa6f1 100644 (file)
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -4396,10 +4396,6 @@ cp_build_binary_op (const op_location_t &location,
   /* True if both operands have arithmetic type.  */
   bool arithmetic_types_p;
 
-  /* Apply default conversions.  */
-  op0 = orig_op0;
-  op1 = orig_op1;
-
   /* Remember whether we're doing / or %.  */
   bool doing_div_or_mod = false;
 
@@ -4409,6 +4405,10 @@ cp_build_binary_op (const op_location_t &location,
   /* Tree holding instrumentation expression.  */
   tree instrument_expr = NULL_TREE;
 
+  /* Apply default conversions.  */
+  op0 = resolve_nondeduced_context (orig_op0, complain);
+  op1 = resolve_nondeduced_context (orig_op1, complain);
+
   if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
       || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
       || code == TRUTH_XOR_EXPR)
@@ -6216,11 +6216,13 @@ cp_build_unary_op (enum tree_code code, tree xarg, bool noconvert,
   if (!arg || error_operand_p (arg))
     return error_mark_node;
 
+  arg = resolve_nondeduced_context (arg, complain);
+
   if ((invalid_op_diag
        = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
                                    ? CONVERT_EXPR
                                    : code),
-                                  TREE_TYPE (xarg))))
+                                  TREE_TYPE (arg))))
     {
       if (complain & tf_error)
        error (invalid_op_diag);

diff --git a/gcc/testsuite/g++.dg/template/operator15.C b/gcc/testsuite/g++.dg/template/operator15.C
new file mode 100644 (file)
index 0000000..7554422
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/operator15.C
@@ -0,0 +1,6 @@
+// PR c++/60531
+
+template < class T > T foo ();
+
+bool b1 = foo<int> == foo<int>;
+int (*fp1)() = +foo<int>;