4 files changed, 20 insertions, 10 deletions
diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index edb165fcc9f..de7cf4fc058 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -374,6 +374,11 @@ ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
 		newa->location = exprLocation((Node *) vargs);
 
 		fargs = lappend(fargs, newa);
+
+		/* We could not have had VARIADIC marking before ... */
+		Assert(!func_variadic);
+		/* ... but now, it's a VARIADIC call */
+		func_variadic = true;
 	}
 
 	/* build the appropriate output structure */
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 71798efc436..eca03cb82de 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -8604,7 +8604,7 @@ generate_relation_name(Oid relid, List *namespaces)
  *
  * If we're dealing with a potentially variadic function (in practice, this
  * means a FuncExpr and not some other way of calling the function), then
- * was_variadic must specify whether VARIADIC appeared in the original call,
+ * was_variadic should specify whether variadic arguments have been merged,
  * and *use_variadic_p will be set to indicate whether to print VARIADIC in
  * the output.	For non-FuncExpr cases, was_variadic should be FALSE and
  * use_variadic_p can be NULL.
@@ -8639,14 +8639,16 @@ generate_function_name(Oid funcid, int nargs, List *argnames, Oid *argtypes,
 	 * since it affects the lookup rules in func_get_detail().
 	 *
 	 * Currently, we always print VARIADIC if the function is variadic and
-	 * takes a variadic type other than ANY.  (In principle, if VARIADIC
-	 * wasn't originally specified and the array actual argument is
-	 * deconstructable, we could print the array elements separately and not
-	 * print VARIADIC, thus more nearly reproducing the original input.  For
-	 * the moment that seems like too much complication for the benefit.)
-	 * However, if the function takes VARIADIC ANY, then the parser didn't
-	 * fold the arguments together into an array, so we must print VARIADIC if
-	 * and only if it was used originally.
+	 * takes a variadic type other than ANY.  However, if the function takes
+	 * VARIADIC ANY, then the parser didn't fold the arguments together into
+	 * an array, so we must print VARIADIC if and only if it was used
+	 * originally.
+	 *
+	 * Note: with the current definition of funcvariadic, we could just set
+	 * use_variadic = was_variadic, which indeed is the solution adopted in
+	 * 9.4.  However, in rules/views stored before 9.3.5, funcvariadic will
+	 * reflect the previous definition (was VARIADIC written in the call?).
+	 * So in 9.3 we cannot trust it unless the function is VARIADIC ANY.
 	 */
 	if (use_variadic_p)
 	{
diff --git a/src/backend/utils/fmgr/fmgr.c b/src/backend/utils/fmgr/fmgr.c
index 675213064b8..778f75aefcd 100644
--- a/src/backend/utils/fmgr/fmgr.c
+++ b/src/backend/utils/fmgr/fmgr.c
@@ -2452,6 +2452,8 @@ get_call_expr_arg_stable(Node *expr, int argnum)
  * Get the VARIADIC flag from the function invocation
  *
  * Returns false (the default assumption) if information is not available
+ *
+ * Note this is generally only of interest to VARIADIC ANY functions
  */
 bool
 get_fn_expr_variadic(FmgrInfo *flinfo)
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index 75b716a9671..c17b74e4b12 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -346,7 +346,8 @@ typedef struct FuncExpr
 	Oid			funcid;			/* PG_PROC OID of the function */
 	Oid			funcresulttype; /* PG_TYPE OID of result value */
 	bool		funcretset;		/* true if function returns set */
-	bool		funcvariadic;	/* true if VARIADIC was used in call */
+	bool		funcvariadic;	/* true if variadic arguments have been
+								 * combined into an array last argument */
 	CoercionForm funcformat;	/* how to display this function call */
 	Oid			funccollid;		/* OID of collation of result */
 	Oid			inputcollid;	/* OID of collation that function should use */