Introduce "anycompatible" family of polymorphic types.

This patch adds the pseudo-types anycompatible, anycompatiblearray,
anycompatiblenonarray, and anycompatiblerange.  They work much like
anyelement, anyarray, anynonarray, and anyrange respectively, except
that the actual input values need not match precisely in type.
Instead, if we can find a common supertype (using the same rules
as for UNION/CASE type resolution), then the parser automatically
promotes the input values to that type.  For example,
"myfunc(anycompatible, anycompatible)" can match a call with one
integer and one bigint argument, with the integer automatically
promoted to bigint.  With anyelement in the definition, the user
would have had to cast the integer explicitly.

The new types also provide a second, independent set of type variables
for function matching; thus with "myfunc(anyelement, anyelement,
anycompatible) returns anycompatible" the first two arguments are
constrained to be the same type, but the third can be some other
type, and the result has the type of the third argument.  The need
for more than one set of type variables was foreseen back when we
first invented the polymorphic types, but we never did anything
about it.

Pavel Stehule, revised a bit by me

Discussion: https://postgr.es/m/CAFj8pRDna7VqNi8gR+Tt2Ktmz0cq5G93guc3Sbn_NVPLdXAkqA@mail.gmail.com

29 files changed, 1742 insertions, 82 deletions

diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index 023ec7e6188..2d81bc3cbc9 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -404,10 +404,6 @@ ConstructTupleDescriptor(Relation heapRelation,
 		 */
 		keyType = amroutine->amkeytype;
 
-		/*
-		 * Code below is concerned to the opclasses which are not used with
-		 * the included columns.
-		 */
 		if (i < indexInfo->ii_NumIndexKeyAttrs)
 		{
 			tuple = SearchSysCache1(CLAOID, ObjectIdGetDatum(classObjectId[i]));
@@ -422,6 +418,10 @@ ConstructTupleDescriptor(Relation heapRelation,
 			 * If keytype is specified as ANYELEMENT, and opcintype is
 			 * ANYARRAY, then the attribute type must be an array (else it'd
 			 * not have matched this opclass); use its element type.
+			 *
+			 * We could also allow ANYCOMPATIBLE/ANYCOMPATIBLEARRAY here, but
+			 * there seems no need to do so; there's no reason to declare an
+			 * opclass as taking ANYCOMPATIBLEARRAY rather than ANYARRAY.
 			 */
 			if (keyType == ANYELEMENTOID && opclassTup->opcintype == ANYARRAYOID)
 			{
diff --git a/src/backend/catalog/pg_proc.c b/src/backend/catalog/pg_proc.c
index 0cac936cef8..6cdda35d1c9 100644
--- a/src/backend/catalog/pg_proc.c
+++ b/src/backend/catalog/pg_proc.c
@@ -262,6 +262,9 @@ ProcedureCreate(const char *procedureName,
 						case ANYARRAYOID:
 							variadicType = ANYELEMENTOID;
 							break;
+						case ANYCOMPATIBLEARRAYOID:
+							variadicType = ANYCOMPATIBLEOID;
+							break;
 						default:
 							variadicType = get_element_type(allParams[i]);
 							if (!OidIsValid(variadicType))
diff --git a/src/backend/commands/functioncmds.c b/src/backend/commands/functioncmds.c
index 5eac55aaca1..694114adedc 100644
--- a/src/backend/commands/functioncmds.c
+++ b/src/backend/commands/functioncmds.c
@@ -320,6 +320,7 @@ interpret_function_parameter_list(ParseState *pstate,
 			switch (toid)
 			{
 				case ANYARRAYOID:
+				case ANYCOMPATIBLEARRAYOID:
 				case ANYOID:
 					/* okay */
 					break;
diff --git a/src/backend/parser/parse_coerce.c b/src/backend/parser/parse_coerce.c
index c3fb51d35d9..645e4aa4ceb 100644
--- a/src/backend/parser/parse_coerce.c
+++ b/src/backend/parser/parse_coerce.c
@@ -167,15 +167,17 @@ coerce_type(ParseState *pstate, Node *node,
 	}
 	if (targetTypeId == ANYOID ||
 		targetTypeId == ANYELEMENTOID ||
-		targetTypeId == ANYNONARRAYOID)
+		targetTypeId == ANYNONARRAYOID ||
+		targetTypeId == ANYCOMPATIBLEOID ||
+		targetTypeId == ANYCOMPATIBLENONARRAYOID)
 	{
 		/*
 		 * Assume can_coerce_type verified that implicit coercion is okay.
 		 *
 		 * Note: by returning the unmodified node here, we are saying that
 		 * it's OK to treat an UNKNOWN constant as a valid input for a
-		 * function accepting ANY, ANYELEMENT, or ANYNONARRAY.  This should be
-		 * all right, since an UNKNOWN value is still a perfectly valid Datum.
+		 * function accepting one of these pseudotypes.  This should be all
+		 * right, since an UNKNOWN value is still a perfectly valid Datum.
 		 *
 		 * NB: we do NOT want a RelabelType here: the exposed type of the
 		 * function argument must be its actual type, not the polymorphic
@@ -185,7 +187,9 @@ coerce_type(ParseState *pstate, Node *node,
 	}
 	if (targetTypeId == ANYARRAYOID ||
 		targetTypeId == ANYENUMOID ||
-		targetTypeId == ANYRANGEOID)
+		targetTypeId == ANYRANGEOID ||
+		targetTypeId == ANYCOMPATIBLEARRAYOID ||
+		targetTypeId == ANYCOMPATIBLERANGEOID)
 	{
 		/*
 		 * Assume can_coerce_type verified that implicit coercion is okay.
@@ -193,10 +197,10 @@ coerce_type(ParseState *pstate, Node *node,
 		 * These cases are unlike the ones above because the exposed type of
 		 * the argument must be an actual array, enum, or range type.  In
 		 * particular the argument must *not* be an UNKNOWN constant.  If it
-		 * is, we just fall through; below, we'll call anyarray_in,
-		 * anyenum_in, or anyrange_in, which will produce an error.  Also, if
-		 * what we have is a domain over array, enum, or range, we have to
-		 * relabel it to its base type.
+		 * is, we just fall through; below, we'll call the pseudotype's input
+		 * function, which will produce an error.  Also, if what we have is a
+		 * domain over array, enum, or range, we have to relabel it to its
+		 * base type.
 		 *
 		 * Note: currently, we can't actually see a domain-over-enum here,
 		 * since the other functions in this file will not match such a
@@ -1387,6 +1391,103 @@ select_common_type(ParseState *pstate, List *exprs, const char *context,
 }
 
 /*
+ * select_common_type_from_oids()
+ *		Determine the common supertype of an array of type OIDs.
+ *
+ * This is the same logic as select_common_type(), but working from
+ * an array of type OIDs not a list of expressions.  As in that function,
+ * earlier entries in the array have some preference over later ones.
+ * On failure, return InvalidOid if noerror is true, else throw an error.
+ *
+ * Note: neither caller will pass any UNKNOWNOID entries, so the tests
+ * for that in this function are dead code.  However, they don't cost much,
+ * and it seems better to keep this logic as close to select_common_type()
+ * as possible.
+ */
+static Oid
+select_common_type_from_oids(int nargs, const Oid *typeids, bool noerror)
+{
+	Oid			ptype;
+	TYPCATEGORY pcategory;
+	bool		pispreferred;
+	int			i = 1;
+
+	Assert(nargs > 0);
+	ptype = typeids[0];
+
+	/* If all input types are valid and exactly the same, pick that type. */
+	if (ptype != UNKNOWNOID)
+	{
+		for (; i < nargs; i++)
+		{
+			if (typeids[i] != ptype)
+				break;
+		}
+		if (i == nargs)
+			return ptype;
+	}
+
+	/*
+	 * Nope, so set up for the full algorithm.  Note that at this point, we
+	 * can skip array entries before "i"; they are all equal to ptype.
+	 */
+	ptype = getBaseType(ptype);
+	get_type_category_preferred(ptype, &pcategory, &pispreferred);
+
+	for (; i < nargs; i++)
+	{
+		Oid			ntype = getBaseType(typeids[i]);
+
+		/* move on to next one if no new information... */
+		if (ntype != UNKNOWNOID && ntype != ptype)
+		{
+			TYPCATEGORY ncategory;
+			bool		nispreferred;
+
+			get_type_category_preferred(ntype, &ncategory, &nispreferred);
+			if (ptype == UNKNOWNOID)
+			{
+				/* so far, only unknowns so take anything... */
+				ptype = ntype;
+				pcategory = ncategory;
+				pispreferred = nispreferred;
+			}
+			else if (ncategory != pcategory)
+			{
+				/*
+				 * both types in different categories? then not much hope...
+				 */
+				if (noerror)
+					return InvalidOid;
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("argument types %s and %s cannot be matched",
+								format_type_be(ptype),
+								format_type_be(ntype))));
+			}
+			else if (!pispreferred &&
+					 can_coerce_type(1, &ptype, &ntype, COERCION_IMPLICIT) &&
+					 !can_coerce_type(1, &ntype, &ptype, COERCION_IMPLICIT))
+			{
+				/*
+				 * take new type if can coerce to it implicitly but not the
+				 * other way; but if we have a preferred type, stay on it.
+				 */
+				ptype = ntype;
+				pcategory = ncategory;
+				pispreferred = nispreferred;
+			}
+		}
+	}
+
+	/* Like select_common_type(), choose TEXT if all inputs were UNKNOWN */
+	if (ptype == UNKNOWNOID)
+		ptype = TEXTOID;
+
+	return ptype;
+}
+
+/*
  * coerce_to_common_type()
  *		Coerce an expression to the given type.
  *
@@ -1442,14 +1543,28 @@ coerce_to_common_type(ParseState *pstate, Node *node,
  *	  we add the extra condition that the ANYELEMENT type must not be an array.
  *	  (This is a no-op if used in combination with ANYARRAY or ANYENUM, but
  *	  is an extra restriction if not.)
+ * 7) All arguments declared ANYCOMPATIBLE must be implicitly castable
+ *	  to a common supertype (chosen as per select_common_type's rules).
+ *	  ANYCOMPATIBLENONARRAY works like ANYCOMPATIBLE but also requires the
+ *	  common supertype to not be an array.  If there are ANYCOMPATIBLEARRAY
+ *	  or ANYCOMPATIBLERANGE arguments, their element types or subtypes are
+ *	  included while making the choice of common supertype.
+ * 8) The resolved type of ANYCOMPATIBLEARRAY arguments will be the array
+ *	  type over the common supertype (which might not be the same array type
+ *	  as any of the original arrays).
+ * 9) All ANYCOMPATIBLERANGE arguments must be the exact same range type
+ *	  (after domain flattening), since we have no preference rule that would
+ *	  let us choose one over another.  Furthermore, that range's subtype
+ *	  must exactly match the common supertype chosen by rule 7.
  *
  * Domains over arrays match ANYARRAY, and are immediately flattened to their
  * base type.  (Thus, for example, we will consider it a match if one ANYARRAY
  * argument is a domain over int4[] while another one is just int4[].)	Also
- * notice that such a domain does *not* match ANYNONARRAY.
+ * notice that such a domain does *not* match ANYNONARRAY.  The same goes
+ * for ANYCOMPATIBLEARRAY and ANYCOMPATIBLENONARRAY.
  *
- * Similarly, domains over ranges match ANYRANGE, and are immediately
- * flattened to their base type.
+ * Similarly, domains over ranges match ANYRANGE or ANYCOMPATIBLERANGE,
+ * and are immediately flattened to their base type.
  *
  * Note that domains aren't currently considered to match ANYENUM,
  * even if their base type would match.
@@ -1467,13 +1582,19 @@ check_generic_type_consistency(const Oid *actual_arg_types,
 	Oid			elem_typeid = InvalidOid;
 	Oid			array_typeid = InvalidOid;
 	Oid			range_typeid = InvalidOid;
+	Oid			anycompatible_range_typeid = InvalidOid;
+	Oid			anycompatible_range_typelem = InvalidOid;
 	bool		have_anynonarray = false;
 	bool		have_anyenum = false;
+	bool		have_anycompatible_nonarray = false;
+	int			n_anycompatible_args = 0;
+	Oid			anycompatible_actual_types[FUNC_MAX_ARGS];
 
 	/*
 	 * Loop through the arguments to see if we have any that are polymorphic.
 	 * If so, require the actual types to be consistent.
 	 */
+	Assert(nargs <= FUNC_MAX_ARGS);
 	for (int j = 0; j < nargs; j++)
 	{
 		Oid			decl_type = declared_arg_types[j];
@@ -1511,6 +1632,50 @@ check_generic_type_consistency(const Oid *actual_arg_types,
 				return false;
 			range_typeid = actual_type;
 		}
+		else if (decl_type == ANYCOMPATIBLEOID ||
+				 decl_type == ANYCOMPATIBLENONARRAYOID)
+		{
+			if (decl_type == ANYCOMPATIBLENONARRAYOID)
+				have_anycompatible_nonarray = true;
+			if (actual_type == UNKNOWNOID)
+				continue;
+			/* collect the actual types of non-unknown COMPATIBLE args */
+			anycompatible_actual_types[n_anycompatible_args++] = actual_type;
+		}
+		else if (decl_type == ANYCOMPATIBLEARRAYOID)
+		{
+			Oid			elem_type;
+
+			if (actual_type == UNKNOWNOID)
+				continue;
+			actual_type = getBaseType(actual_type); /* flatten domains */
+			elem_type = get_element_type(actual_type);
+			if (!OidIsValid(elem_type))
+				return false;	/* not an array */
+			/* collect the element type for common-supertype choice */
+			anycompatible_actual_types[n_anycompatible_args++] = elem_type;
+		}
+		else if (decl_type == ANYCOMPATIBLERANGEOID)
+		{
+			if (actual_type == UNKNOWNOID)
+				continue;
+			actual_type = getBaseType(actual_type); /* flatten domains */
+			if (OidIsValid(anycompatible_range_typeid))
+			{
+				/* All ANYCOMPATIBLERANGE arguments must be the same type */
+				if (anycompatible_range_typeid != actual_type)
+					return false;
+			}
+			else
+			{
+				anycompatible_range_typeid = actual_type;
+				anycompatible_range_typelem = get_range_subtype(actual_type);
+				if (!OidIsValid(anycompatible_range_typelem))
+					return false;	/* not a range type */
+				/* collect the subtype for common-supertype choice */
+				anycompatible_actual_types[n_anycompatible_args++] = anycompatible_range_typelem;
+			}
+		}
 	}
 
 	/* Get the element type based on the array type, if we have one */
@@ -1591,6 +1756,38 @@ check_generic_type_consistency(const Oid *actual_arg_types,
 			return false;
 	}
 
+	/* Check matching of ANYCOMPATIBLE-family arguments, if any */
+	if (n_anycompatible_args > 0)
+	{
+		Oid			anycompatible_typeid;
+
+		anycompatible_typeid =
+			select_common_type_from_oids(n_anycompatible_args,
+										 anycompatible_actual_types,
+										 true);
+
+		if (!OidIsValid(anycompatible_typeid))
+			return false;		/* there's no common supertype */
+
+		if (have_anycompatible_nonarray)
+		{
+			/*
+			 * require the anycompatible type to not be an array or domain
+			 * over array
+			 */
+			if (type_is_array_domain(anycompatible_typeid))
+				return false;
+		}
+
+		/*
+		 * the anycompatible type must exactly match the range element type,
+		 * if we were able to identify one
+		 */
+		if (OidIsValid(anycompatible_range_typelem) &&
+			anycompatible_range_typelem != anycompatible_typeid)
+			return false;
+	}
+
 	/* Looks valid */
 	return true;
 }
@@ -1610,6 +1807,11 @@ check_generic_type_consistency(const Oid *actual_arg_types,
  * successful, we alter that position of declared_arg_types[] so that
  * make_fn_arguments will coerce the literal to the right thing.
  *
+ * If we have polymorphic arguments of the ANYCOMPATIBLE family,
+ * we similarly alter declared_arg_types[] entries to show the resolved
+ * common supertype, so that make_fn_arguments will coerce the actual
+ * arguments to the proper type.
+ *
  * Rules are applied to the function's return type (possibly altering it)
  * if it is declared as a polymorphic type:
  *
@@ -1631,11 +1833,20 @@ check_generic_type_consistency(const Oid *actual_arg_types,
  *	  we add the extra condition that the ANYELEMENT type must not be an array.
  *	  (This is a no-op if used in combination with ANYARRAY or ANYENUM, but
  *	  is an extra restriction if not.)
+ * 8) ANYCOMPATIBLE, ANYCOMPATIBLEARRAY, ANYCOMPATIBLENONARRAY, and
+ *	  ANYCOMPATIBLERANGE are handled by resolving the common supertype
+ *	  of those arguments (or their element types/subtypes, for array and range
+ *	  inputs), and then coercing all those arguments to the common supertype,
+ *	  or the array type over the common supertype for ANYCOMPATIBLEARRAY.
+ *	  For ANYCOMPATIBLERANGE, there must be at least one non-UNKNOWN input,
+ *	  all such inputs must be the same range type, and that type's subtype
+ *	  must equal the common supertype.
  *
  * Domains over arrays or ranges match ANYARRAY or ANYRANGE arguments,
  * respectively, and are immediately flattened to their base type.  (In
  * particular, if the return type is also ANYARRAY or ANYRANGE, we'll set
- * it to the base type not the domain type.)
+ * it to the base type not the domain type.)  The same is true for
+ * ANYCOMPATIBLEARRAY and ANYCOMPATIBLERANGE.
  *
  * When allow_poly is false, we are not expecting any of the actual_arg_types
  * to be polymorphic, and we should not return a polymorphic result type
@@ -1652,7 +1863,12 @@ check_generic_type_consistency(const Oid *actual_arg_types,
  * the element type to infer the result type.  Note this means that functions
  * taking ANYARRAY had better behave sanely if applied to the pg_statistic
  * columns; they can't just assume that successive inputs are of the same
- * actual element type.
+ * actual element type.  There is no similar logic for ANYCOMPATIBLEARRAY;
+ * there isn't a need for it since there are no catalog columns of that type,
+ * so we won't see it as input.  We could consider matching an actual ANYARRAY
+ * input to an ANYCOMPATIBLEARRAY argument, but at present that seems useless
+ * as well, since there's no value in using ANYCOMPATIBLEARRAY unless there's
+ * at least one other ANYCOMPATIBLE-family argument or result.
  */
 Oid
 enforce_generic_type_consistency(const Oid *actual_arg_types,
@@ -1661,18 +1877,29 @@ enforce_generic_type_consistency(const Oid *actual_arg_types,
 								 Oid rettype,
 								 bool allow_poly)
 {
+	bool		have_poly_anycompatible = false;
 	bool		have_poly_unknowns = false;
 	Oid			elem_typeid = InvalidOid;
 	Oid			array_typeid = InvalidOid;
 	Oid			range_typeid = InvalidOid;
-	int			n_poly_args = 0;
+	Oid			anycompatible_typeid = InvalidOid;
+	Oid			anycompatible_array_typeid = InvalidOid;
+	Oid			anycompatible_range_typeid = InvalidOid;
+	Oid			anycompatible_range_typelem = InvalidOid;
 	bool		have_anynonarray = (rettype == ANYNONARRAYOID);
 	bool		have_anyenum = (rettype == ANYENUMOID);
+	bool		have_anycompatible_nonarray = (rettype == ANYCOMPATIBLENONARRAYOID);
+	bool		have_anycompatible_array = (rettype == ANYCOMPATIBLEARRAYOID);
+	bool		have_anycompatible_range = (rettype == ANYCOMPATIBLERANGEOID);
+	int			n_poly_args = 0;	/* this counts all family-1 arguments */
+	int			n_anycompatible_args = 0;	/* this counts only non-unknowns */
+	Oid			anycompatible_actual_types[FUNC_MAX_ARGS];
 
 	/*
 	 * Loop through the arguments to see if we have any that are polymorphic.
 	 * If so, require the actual types to be consistent.
 	 */
+	Assert(nargs <= FUNC_MAX_ARGS);
 	for (int j = 0; j < nargs; j++)
 	{
 		Oid			decl_type = declared_arg_types[j];
@@ -1743,18 +1970,87 @@ enforce_generic_type_consistency(const Oid *actual_arg_types,
 								   format_type_be(actual_type))));
 			range_typeid = actual_type;
 		}
+		else if (decl_type == ANYCOMPATIBLEOID ||
+				 decl_type == ANYCOMPATIBLENONARRAYOID)
+		{
+			have_poly_anycompatible = true;
+			if (decl_type == ANYCOMPATIBLENONARRAYOID)
+				have_anycompatible_nonarray = true;
+			if (actual_type == UNKNOWNOID)
+				continue;
+			if (allow_poly && decl_type == actual_type)
+				continue;		/* no new information here */
+			/* collect the actual types of non-unknown COMPATIBLE args */
+			anycompatible_actual_types[n_anycompatible_args++] = actual_type;
+		}
+		else if (decl_type == ANYCOMPATIBLEARRAYOID)
+		{
+			Oid			anycompatible_elem_type;
+
+			have_poly_anycompatible = true;
+			have_anycompatible_array = true;
+			if (actual_type == UNKNOWNOID)
+				continue;
+			if (allow_poly && decl_type == actual_type)
+				continue;		/* no new information here */
+			actual_type = getBaseType(actual_type); /* flatten domains */
+			anycompatible_elem_type = get_element_type(actual_type);
+			if (!OidIsValid(anycompatible_elem_type))
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("argument declared %s is not an array but type %s",
+								"anycompatiblearray",
+								format_type_be(actual_type))));
+			/* collect the element type for common-supertype choice */
+			anycompatible_actual_types[n_anycompatible_args++] = anycompatible_elem_type;
+		}
+		else if (decl_type == ANYCOMPATIBLERANGEOID)
+		{
+			have_poly_anycompatible = true;
+			have_anycompatible_range = true;
+			if (actual_type == UNKNOWNOID)
+				continue;
+			if (allow_poly && decl_type == actual_type)
+				continue;		/* no new information here */
+			actual_type = getBaseType(actual_type); /* flatten domains */
+			if (OidIsValid(anycompatible_range_typeid))
+			{
+				/* All ANYCOMPATIBLERANGE arguments must be the same type */
+				if (anycompatible_range_typeid != actual_type)
+					ereport(ERROR,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("arguments declared \"anycompatiblerange\" are not all alike"),
+							 errdetail("%s versus %s",
+									   format_type_be(anycompatible_range_typeid),
+									   format_type_be(actual_type))));
+			}
+			else
+			{
+				anycompatible_range_typeid = actual_type;
+				anycompatible_range_typelem = get_range_subtype(actual_type);
+				if (!OidIsValid(anycompatible_range_typelem))
+					ereport(ERROR,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("argument declared %s is not a range type but type %s",
+									"anycompatiblerange",
+									format_type_be(actual_type))));
+				/* collect the subtype for common-supertype choice */
+				anycompatible_actual_types[n_anycompatible_args++] = anycompatible_range_typelem;
+			}
+		}
 	}
 
 	/*
 	 * Fast Track: if none of the arguments are polymorphic, return the
 	 * unmodified rettype.  We assume it can't be polymorphic either.
 	 */
-	if (n_poly_args == 0)
+	if (n_poly_args == 0 && !have_poly_anycompatible)
 	{
 		Assert(!IsPolymorphicType(rettype));
 		return rettype;
 	}
 
+	/* Check matching of family-1 polymorphic arguments, if any */
 	if (n_poly_args)
 	{
 		/* Get the element type based on the array type, if we have one */
@@ -1766,13 +2062,14 @@ enforce_generic_type_consistency(const Oid *actual_arg_types,
 			{
 				/*
 				 * Special case for matching ANYARRAY input to an ANYARRAY
-				 * argument: allow it iff no other arguments are polymorphic
-				 * (otherwise we couldn't be sure whether the array element
-				 * type matches up) and the result type doesn't require us to
-				 * infer a specific element type.
+				 * argument: allow it iff no other arguments are family-1
+				 * polymorphics (otherwise we couldn't be sure whether the
+				 * array element type matches up) and the result type doesn't
+				 * require us to infer a specific element type.
 				 */
 				if (n_poly_args != 1 ||
-					(rettype != ANYARRAYOID && IsPolymorphicType(rettype)))
+					(rettype != ANYARRAYOID &&
+					 IsPolymorphicTypeFamily1(rettype)))
 					ereport(ERROR,
 							(errcode(ERRCODE_DATATYPE_MISMATCH),
 							 errmsg("cannot determine element type of \"anyarray\" argument")));
@@ -1888,9 +2185,108 @@ enforce_generic_type_consistency(const Oid *actual_arg_types,
 		}
 	}
 
+	/* Check matching of family-2 polymorphic arguments, if any */
+	if (have_poly_anycompatible)
+	{
+		if (n_anycompatible_args > 0)
+		{
+			anycompatible_typeid =
+				select_common_type_from_oids(n_anycompatible_args,
+											 anycompatible_actual_types,
+											 false);
+
+			if (have_anycompatible_array)
+			{
+				anycompatible_array_typeid = get_array_type(anycompatible_typeid);
+				if (!OidIsValid(anycompatible_array_typeid))
+					ereport(ERROR,
+							(errcode(ERRCODE_UNDEFINED_OBJECT),
+							 errmsg("could not find array type for data type %s",
+									format_type_be(anycompatible_typeid))));
+			}
+
+			if (have_anycompatible_range)
+			{
+				/* we can't infer a range type from the others */
+				if (!OidIsValid(anycompatible_range_typeid))
+					ereport(ERROR,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("could not determine polymorphic type %s because input has type %s",
+									"anycompatiblerange", "unknown")));
+
+				/*
+				 * the anycompatible type must exactly match the range element
+				 * type
+				 */
+				if (anycompatible_range_typelem != anycompatible_typeid)
+					ereport(ERROR,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("anycompatiblerange type %s does not match anycompatible type %s",
+									format_type_be(anycompatible_range_typeid),
+									format_type_be(anycompatible_typeid))));
+			}
+
+			if (have_anycompatible_nonarray)
+			{
+				/*
+				 * require the element type to not be an array or domain over
+				 * array
+				 */
+				if (type_is_array_domain(anycompatible_typeid))
+					ereport(ERROR,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("type matched to anycompatiblenonarray is an array type: %s",
+									format_type_be(anycompatible_typeid))));
+			}
+		}
+		else
+		{
+			if (allow_poly)
+			{
+				anycompatible_typeid = ANYCOMPATIBLEOID;
+				anycompatible_array_typeid = ANYCOMPATIBLEARRAYOID;
+				anycompatible_range_typeid = ANYCOMPATIBLERANGEOID;
+			}
+			else
+			{
+				/*
+				 * Only way to get here is if all the ANYCOMPATIBLE args have
+				 * UNKNOWN inputs.  Resolve to TEXT as select_common_type()
+				 * would do.  That doesn't license us to use TEXTRANGE,
+				 * though.
+				 */
+				anycompatible_typeid = TEXTOID;
+				anycompatible_array_typeid = TEXTARRAYOID;
+				if (have_anycompatible_range)
+					ereport(ERROR,
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("could not determine polymorphic type %s because input has type %s",
+									"anycompatiblerange", "unknown")));
+			}
+		}
+
+		/* replace polymorphic types by selected types */
+		for (int j = 0; j < nargs; j++)
+		{
+			Oid			decl_type = declared_arg_types[j];
+
+			if (decl_type == ANYCOMPATIBLEOID ||
+				decl_type == ANYCOMPATIBLENONARRAYOID)
+				declared_arg_types[j] = anycompatible_typeid;
+			else if (decl_type == ANYCOMPATIBLEARRAYOID)
+				declared_arg_types[j] = anycompatible_array_typeid;
+			else if (decl_type == ANYCOMPATIBLERANGEOID)
+				declared_arg_types[j] = anycompatible_range_typeid;
+		}
+	}
+
 	/*
 	 * If we had any UNKNOWN inputs for polymorphic arguments, re-scan to
 	 * assign correct types to them.
+	 *
+	 * Note: we don't have to consider unknown inputs that were matched to
+	 * ANYCOMPATIBLE-family arguments, because we forcibly updated their
+	 * declared_arg_types[] positions just above.
 	 */
 	if (have_poly_unknowns)
 	{
@@ -1923,10 +2319,11 @@ enforce_generic_type_consistency(const Oid *actual_arg_types,
 			{
 				if (!OidIsValid(range_typeid))
 				{
+					/* we can't infer a range type from the others */
 					ereport(ERROR,
-							(errcode(ERRCODE_UNDEFINED_OBJECT),
-							 errmsg("could not find range type for data type %s",
-									format_type_be(elem_typeid))));
+							(errcode(ERRCODE_DATATYPE_MISMATCH),
+							 errmsg("could not determine polymorphic type %s because input has type %s",
+									"anyrange", "unknown")));
 				}
 				declared_arg_types[j] = range_typeid;
 			}
@@ -1957,16 +2354,49 @@ enforce_generic_type_consistency(const Oid *actual_arg_types,
 	/* if we return ANYRANGE use the appropriate argument type */
 	if (rettype == ANYRANGEOID)
 	{
+		/* this error is unreachable if the function signature is valid: */
 		if (!OidIsValid(range_typeid))
-		{
 			ereport(ERROR,
-					(errcode(ERRCODE_UNDEFINED_OBJECT),
-					 errmsg("could not find range type for data type %s",
-							format_type_be(elem_typeid))));
-		}
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("could not determine polymorphic type %s because input has type %s",
+							"anyrange", "unknown")));
 		return range_typeid;
 	}
 
+	/* if we return ANYCOMPATIBLE use the appropriate type */
+	if (rettype == ANYCOMPATIBLEOID ||
+		rettype == ANYCOMPATIBLENONARRAYOID)
+	{
+		/* this error is unreachable if the function signature is valid: */
+		if (!OidIsValid(anycompatible_typeid))
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg_internal("could not identify anycompatible type")));
+		return anycompatible_typeid;
+	}
+
+	/* if we return ANYCOMPATIBLEARRAY use the appropriate type */
+	if (rettype == ANYCOMPATIBLEARRAYOID)
+	{
+		/* this error is unreachable if the function signature is valid: */
+		if (!OidIsValid(anycompatible_array_typeid))
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg_internal("could not identify anycompatiblearray type")));
+		return anycompatible_array_typeid;
+	}
+
+	/* if we return ANYCOMPATIBLERANGE use the appropriate argument type */
+	if (rettype == ANYCOMPATIBLERANGEOID)
+	{
+		/* this error is unreachable if the function signature is valid: */
+		if (!OidIsValid(anycompatible_range_typeid))
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg_internal("could not identify anycompatiblerange type")));
+		return anycompatible_range_typeid;
+	}
+
 	/* we don't return a generic type; send back the original return type */
 	return rettype;
 }
@@ -1984,11 +2414,12 @@ check_valid_polymorphic_signature(Oid ret_type,
 								  const Oid *declared_arg_types,
 								  int nargs)
 {
-	if (ret_type == ANYRANGEOID)
+	if (ret_type == ANYRANGEOID || ret_type == ANYCOMPATIBLERANGEOID)
 	{
 		/*
 		 * ANYRANGE requires an ANYRANGE input, else we can't tell which of
-		 * several range types with the same element type to use.
+		 * several range types with the same element type to use.  Likewise
+		 * for ANYCOMPATIBLERANGE.
 		 */
 		for (int i = 0; i < nargs; i++)
 		{
@@ -1998,17 +2429,30 @@ check_valid_polymorphic_signature(Oid ret_type,
 		return psprintf(_("A result of type %s requires at least one input of type %s."),
 						format_type_be(ret_type), format_type_be(ret_type));
 	}
-	else if (IsPolymorphicType(ret_type))
+	else if (IsPolymorphicTypeFamily1(ret_type))
 	{
-		/* Otherwise, any polymorphic type can be deduced from any other */
+		/* Otherwise, any family-1 type can be deduced from any other */
 		for (int i = 0; i < nargs; i++)
 		{
-			if (IsPolymorphicType(declared_arg_types[i]))
+			if (IsPolymorphicTypeFamily1(declared_arg_types[i]))
 				return NULL;	/* OK */
 		}
+		/* Keep this list in sync with IsPolymorphicTypeFamily1! */
 		return psprintf(_("A result of type %s requires at least one input of type anyelement, anyarray, anynonarray, anyenum, or anyrange."),
 						format_type_be(ret_type));
 	}
+	else if (IsPolymorphicTypeFamily2(ret_type))
+	{
+		/* Otherwise, any family-2 type can be deduced from any other */
+		for (int i = 0; i < nargs; i++)
+		{
+			if (IsPolymorphicTypeFamily2(declared_arg_types[i]))
+				return NULL;	/* OK */
+		}
+		/* Keep this list in sync with IsPolymorphicTypeFamily2! */
+		return psprintf(_("A result of type %s requires at least one input of type anycompatible, anycompatiblearray, anycompatiblenonarray, or anycompatiblerange."),
+						format_type_be(ret_type));
+	}
 	else
 		return NULL;			/* OK, ret_type is not polymorphic */
 }
@@ -2113,8 +2557,9 @@ IsBinaryCoercible(Oid srctype, Oid targettype)
 	if (srctype == targettype)
 		return true;
 
-	/* Anything is coercible to ANY or ANYELEMENT */
-	if (targettype == ANYOID || targettype == ANYELEMENTOID)
+	/* Anything is coercible to ANY or ANYELEMENT or ANYCOMPATIBLE */
+	if (targettype == ANYOID || targettype == ANYELEMENTOID ||
+		targettype == ANYCOMPATIBLEOID)
 		return true;
 
 	/* If srctype is a domain, reduce to its base type */
@@ -2125,13 +2570,13 @@ IsBinaryCoercible(Oid srctype, Oid targettype)
 	if (srctype == targettype)
 		return true;
 
-	/* Also accept any array type as coercible to ANYARRAY */
-	if (targettype == ANYARRAYOID)
+	/* Also accept any array type as coercible to ANY[COMPATIBLE]ARRAY */
+	if (targettype == ANYARRAYOID || targettype == ANYCOMPATIBLEARRAYOID)
 		if (type_is_array(srctype))
 			return true;
 
-	/* Also accept any non-array type as coercible to ANYNONARRAY */
-	if (targettype == ANYNONARRAYOID)
+	/* Also accept any non-array type as coercible to ANY[COMPATIBLE]NONARRAY */
+	if (targettype == ANYNONARRAYOID || targettype == ANYCOMPATIBLENONARRAYOID)
 		if (!type_is_array(srctype))
 			return true;
 
@@ -2140,8 +2585,8 @@ IsBinaryCoercible(Oid srctype, Oid targettype)
 		if (type_is_enum(srctype))
 			return true;
 
-	/* Also accept any range type as coercible to ANYRANGE */
-	if (targettype == ANYRANGEOID)
+	/* Also accept any range type as coercible to ANY[COMPATIBLE]RANGE */
+	if (targettype == ANYRANGEOID || targettype == ANYCOMPATIBLERANGEOID)
 		if (type_is_range(srctype))
 			return true;
 
diff --git a/src/backend/utils/adt/json.c b/src/backend/utils/adt/json.c
index f78420e22dc..8bb00abb6b3 100644
--- a/src/backend/utils/adt/json.c
+++ b/src/backend/utils/adt/json.c
@@ -195,7 +195,7 @@ json_categorize_type(Oid typoid,
 		default:
 			/* Check for arrays and composites */
 			if (OidIsValid(get_element_type(typoid)) || typoid == ANYARRAYOID
-				|| typoid == RECORDARRAYOID)
+				|| typoid == ANYCOMPATIBLEARRAYOID || typoid == RECORDARRAYOID)
 				*tcategory = JSONTYPE_ARRAY;
 			else if (type_is_rowtype(typoid))	/* includes RECORDOID */
 				*tcategory = JSONTYPE_COMPOSITE;
diff --git a/src/backend/utils/adt/jsonb.c b/src/backend/utils/adt/jsonb.c
index b961d294723..1e9ca046c69 100644
--- a/src/backend/utils/adt/jsonb.c
+++ b/src/backend/utils/adt/jsonb.c
@@ -677,7 +677,7 @@ jsonb_categorize_type(Oid typoid,
 		default:
 			/* Check for arrays and composites */
 			if (OidIsValid(get_element_type(typoid)) || typoid == ANYARRAYOID
-				|| typoid == RECORDARRAYOID)
+				|| typoid == ANYCOMPATIBLEARRAYOID || typoid == RECORDARRAYOID)
 				*tcategory = JSONBTYPE_ARRAY;
 			else if (type_is_rowtype(typoid))	/* includes RECORDOID */
 				*tcategory = JSONBTYPE_COMPOSITE;
diff --git a/src/backend/utils/adt/pseudotypes.c b/src/backend/utils/adt/pseudotypes.c
index 9eee03c143a..3d6b2f90935 100644
--- a/src/backend/utils/adt/pseudotypes.c
+++ b/src/backend/utils/adt/pseudotypes.c
@@ -169,6 +169,26 @@ anyarray_send(PG_FUNCTION_ARGS)
 }
 
 /*
+ * anycompatiblearray
+ *
+ * We may as well allow output, since we do for anyarray.
+ */
+PSEUDOTYPE_DUMMY_INPUT_FUNC(anycompatiblearray);
+PSEUDOTYPE_DUMMY_RECEIVE_FUNC(anycompatiblearray);
+
+Datum
+anycompatiblearray_out(PG_FUNCTION_ARGS)
+{
+	return array_out(fcinfo);
+}
+
+Datum
+anycompatiblearray_send(PG_FUNCTION_ARGS)
+{
+	return array_send(fcinfo);
+}
+
+/*
  * anyenum
  *
  * We may as well allow output, since enum_out will in fact work.
@@ -195,6 +215,19 @@ anyrange_out(PG_FUNCTION_ARGS)
 }
 
 /*
+ * anycompatiblerange
+ *
+ * We may as well allow output, since range_out will in fact work.
+ */
+PSEUDOTYPE_DUMMY_INPUT_FUNC(anycompatiblerange);
+
+Datum
+anycompatiblerange_out(PG_FUNCTION_ARGS)
+{
+	return range_out(fcinfo);
+}
+
+/*
  * void
  *
  * We support void_in so that PL functions can return VOID without any
@@ -316,3 +349,5 @@ PSEUDOTYPE_DUMMY_IO_FUNCS(tsm_handler);
 PSEUDOTYPE_DUMMY_IO_FUNCS(internal);
 PSEUDOTYPE_DUMMY_IO_FUNCS(anyelement);
 PSEUDOTYPE_DUMMY_IO_FUNCS(anynonarray);
+PSEUDOTYPE_DUMMY_IO_FUNCS(anycompatible);
+PSEUDOTYPE_DUMMY_IO_FUNCS(anycompatiblenonarray);
diff --git a/src/backend/utils/fmgr/funcapi.c b/src/backend/utils/fmgr/funcapi.c
index 4e9d21bd541..78ed8572038 100644
--- a/src/backend/utils/fmgr/funcapi.c
+++ b/src/backend/utils/fmgr/funcapi.c
@@ -552,7 +552,9 @@ resolve_anyrange_from_others(polymorphic_actuals *actuals)
  * with concrete data types deduced from the input arguments.
  * declared_args is an oidvector of the function's declared input arg types
  * (showing which are polymorphic), and call_expr is the call expression.
- * Returns true if able to deduce all types, false if not.
+ *
+ * Returns true if able to deduce all types, false if necessary information
+ * is not provided (call_expr is NULL or arg types aren't identifiable).
  */
 static bool
 resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
@@ -564,8 +566,13 @@ resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
 	bool		have_anyelement_result = false;
 	bool		have_anyarray_result = false;
 	bool		have_anyrange_result = false;
+	bool		have_anycompatible_result = false;
+	bool		have_anycompatible_array_result = false;
+	bool		have_anycompatible_range_result = false;
 	polymorphic_actuals poly_actuals;
+	polymorphic_actuals anyc_actuals;
 	Oid			anycollation = InvalidOid;
+	Oid			anycompatcollation = InvalidOid;
 	int			i;
 
 	/* See if there are any polymorphic outputs; quick out if not */
@@ -587,6 +594,19 @@ resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
 				have_polymorphic_result = true;
 				have_anyrange_result = true;
 				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				have_polymorphic_result = true;
+				have_anycompatible_result = true;
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				have_polymorphic_result = true;
+				have_anycompatible_array_result = true;
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				have_polymorphic_result = true;
+				have_anycompatible_range_result = true;
+				break;
 			default:
 				break;
 		}
@@ -596,12 +616,16 @@ resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
 
 	/*
 	 * Otherwise, extract actual datatype(s) from input arguments.  (We assume
-	 * the parser already validated consistency of the arguments.)
+	 * the parser already validated consistency of the arguments.  Also, for
+	 * the ANYCOMPATIBLE pseudotype family, we expect that all matching
+	 * arguments were coerced to the selected common supertype, so that it
+	 * doesn't matter which one's exposed type we look at.)
 	 */
 	if (!call_expr)
 		return false;			/* no hope */
 
 	memset(&poly_actuals, 0, sizeof(poly_actuals));
+	memset(&anyc_actuals, 0, sizeof(anyc_actuals));
 
 	for (i = 0; i < nargs; i++)
 	{
@@ -636,6 +660,34 @@ resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
 						return false;
 				}
 				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				if (!OidIsValid(anyc_actuals.anyelement_type))
+				{
+					anyc_actuals.anyelement_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(anyc_actuals.anyelement_type))
+						return false;
+				}
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				if (!OidIsValid(anyc_actuals.anyarray_type))
+				{
+					anyc_actuals.anyarray_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(anyc_actuals.anyarray_type))
+						return false;
+				}
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				if (!OidIsValid(anyc_actuals.anyrange_type))
+				{
+					anyc_actuals.anyrange_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(anyc_actuals.anyrange_type))
+						return false;
+				}
+				break;
 			default:
 				break;
 		}
@@ -651,18 +703,33 @@ resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
 	if (have_anyrange_result && !OidIsValid(poly_actuals.anyrange_type))
 		resolve_anyrange_from_others(&poly_actuals);
 
+	if (have_anycompatible_result && !OidIsValid(anyc_actuals.anyelement_type))
+		resolve_anyelement_from_others(&anyc_actuals);
+
+	if (have_anycompatible_array_result && !OidIsValid(anyc_actuals.anyarray_type))
+		resolve_anyarray_from_others(&anyc_actuals);
+
+	if (have_anycompatible_range_result && !OidIsValid(anyc_actuals.anyrange_type))
+		resolve_anyrange_from_others(&anyc_actuals);
+
 	/*
 	 * Identify the collation to use for polymorphic OUT parameters. (It'll
-	 * necessarily be the same for both anyelement and anyarray.)  Note that
-	 * range types are not collatable, so any possible internal collation of a
-	 * range type is not considered here.
+	 * necessarily be the same for both anyelement and anyarray, likewise for
+	 * anycompatible and anycompatiblearray.)  Note that range types are not
+	 * collatable, so any possible internal collation of a range type is not
+	 * considered here.
 	 */
 	if (OidIsValid(poly_actuals.anyelement_type))
 		anycollation = get_typcollation(poly_actuals.anyelement_type);
 	else if (OidIsValid(poly_actuals.anyarray_type))
 		anycollation = get_typcollation(poly_actuals.anyarray_type);
 
-	if (OidIsValid(anycollation))
+	if (OidIsValid(anyc_actuals.anyelement_type))
+		anycompatcollation = get_typcollation(anyc_actuals.anyelement_type);
+	else if (OidIsValid(anyc_actuals.anyarray_type))
+		anycompatcollation = get_typcollation(anyc_actuals.anyarray_type);
+
+	if (OidIsValid(anycollation) || OidIsValid(anycompatcollation))
 	{
 		/*
 		 * The types are collatable, so consider whether to use a nondefault
@@ -672,7 +739,12 @@ resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
 		Oid			inputcollation = exprInputCollation(call_expr);
 
 		if (OidIsValid(inputcollation))
-			anycollation = inputcollation;
+		{
+			if (OidIsValid(anycollation))
+				anycollation = inputcollation;
+			if (OidIsValid(anycompatcollation))
+				anycompatcollation = inputcollation;
+		}
 	}
 
 	/* And finally replace the tuple column types as needed */
@@ -708,6 +780,31 @@ resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
 								   0);
 				/* no collation should be attached to a range type */
 				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   anyc_actuals.anyelement_type,
+								   -1,
+								   0);
+				TupleDescInitEntryCollation(tupdesc, i + 1, anycompatcollation);
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   anyc_actuals.anyarray_type,
+								   -1,
+								   0);
+				TupleDescInitEntryCollation(tupdesc, i + 1, anycompatcollation);
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   anyc_actuals.anyrange_type,
+								   -1,
+								   0);
+				/* no collation should be attached to a range type */
+				break;
 			default:
 				break;
 		}
@@ -720,7 +817,9 @@ resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
  * Given the declared argument types and modes for a function, replace any
  * polymorphic types (ANYELEMENT etc) in argtypes[] with concrete data types
  * deduced from the input arguments found in call_expr.
- * Returns true if able to deduce all types, false if not.
+ *
+ * Returns true if able to deduce all types, false if necessary information
+ * is not provided (call_expr is NULL or arg types aren't identifiable).
  *
  * This is the same logic as resolve_polymorphic_tupdesc, but with a different
  * argument representation, and slightly different output responsibilities.
@@ -735,16 +834,21 @@ resolve_polymorphic_argtypes(int numargs, Oid *argtypes, char *argmodes,
 	bool		have_anyelement_result = false;
 	bool		have_anyarray_result = false;
 	bool		have_anyrange_result = false;
+	bool		have_anycompatible_result = false;
+	bool		have_anycompatible_array_result = false;
+	bool		have_anycompatible_range_result = false;
 	polymorphic_actuals poly_actuals;
+	polymorphic_actuals anyc_actuals;
 	int			inargno;
 	int			i;
 
 	/*
 	 * First pass: resolve polymorphic inputs, check for outputs.  As in
 	 * resolve_polymorphic_tupdesc, we rely on the parser to have enforced
-	 * type consistency.
+	 * type consistency and coerced ANYCOMPATIBLE args to a common supertype.
 	 */
 	memset(&poly_actuals, 0, sizeof(poly_actuals));
+	memset(&anyc_actuals, 0, sizeof(anyc_actuals));
 	inargno = 0;
 	for (i = 0; i < numargs; i++)
 	{
@@ -808,6 +912,61 @@ resolve_polymorphic_argtypes(int numargs, Oid *argtypes, char *argmodes,
 					argtypes[i] = poly_actuals.anyrange_type;
 				}
 				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anycompatible_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(anyc_actuals.anyelement_type))
+					{
+						anyc_actuals.anyelement_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(anyc_actuals.anyelement_type))
+							return false;
+					}
+					argtypes[i] = anyc_actuals.anyelement_type;
+				}
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anycompatible_array_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(anyc_actuals.anyarray_type))
+					{
+						anyc_actuals.anyarray_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(anyc_actuals.anyarray_type))
+							return false;
+					}
+					argtypes[i] = anyc_actuals.anyarray_type;
+				}
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anycompatible_range_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(anyc_actuals.anyrange_type))
+					{
+						anyc_actuals.anyrange_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(anyc_actuals.anyrange_type))
+							return false;
+					}
+					argtypes[i] = anyc_actuals.anyrange_type;
+				}
+				break;
 			default:
 				break;
 		}
@@ -829,6 +988,15 @@ resolve_polymorphic_argtypes(int numargs, Oid *argtypes, char *argmodes,
 	if (have_anyrange_result && !OidIsValid(poly_actuals.anyrange_type))
 		resolve_anyrange_from_others(&poly_actuals);
 
+	if (have_anycompatible_result && !OidIsValid(anyc_actuals.anyelement_type))
+		resolve_anyelement_from_others(&anyc_actuals);
+
+	if (have_anycompatible_array_result && !OidIsValid(anyc_actuals.anyarray_type))
+		resolve_anyarray_from_others(&anyc_actuals);
+
+	if (have_anycompatible_range_result && !OidIsValid(anyc_actuals.anyrange_type))
+		resolve_anyrange_from_others(&anyc_actuals);
+
 	/* And finally replace the output column types as needed */
 	for (i = 0; i < numargs; i++)
 	{
@@ -845,6 +1013,16 @@ resolve_polymorphic_argtypes(int numargs, Oid *argtypes, char *argmodes,
 			case ANYRANGEOID:
 				argtypes[i] = poly_actuals.anyrange_type;
 				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				argtypes[i] = anyc_actuals.anyelement_type;
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				argtypes[i] = anyc_actuals.anyarray_type;
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				argtypes[i] = anyc_actuals.anyrange_type;
+				break;
 			default:
 				break;
 		}
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 3fee9342cc1..50069bea0e1 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202003181
+#define CATALOG_VERSION_NO	202003191
 
 #endif
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index a64378b0027..87d25d4a4bd 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -6673,8 +6673,9 @@
   proname => 'regcollationout', provolatile => 's', prorettype => 'cstring',
   proargtypes => 'regcollation', prosrc => 'regcollationout' },
 { oid => '4195', descr => 'convert classname to regcollation',
-  proname => 'to_regcollation', provolatile => 's', prorettype => 'regcollation',
-  proargtypes => 'text', prosrc => 'to_regcollation' },
+  proname => 'to_regcollation', provolatile => 's',
+  prorettype => 'regcollation', proargtypes => 'text',
+  prosrc => 'to_regcollation' },
 { oid => '2220', descr => 'I/O',
   proname => 'regtypein', provolatile => 's', prorettype => 'regtype',
   proargtypes => 'cstring', prosrc => 'regtypein' },
@@ -7115,6 +7116,42 @@
 { oid => '268', descr => 'I/O',
   proname => 'table_am_handler_out', prorettype => 'cstring',
   proargtypes => 'table_am_handler', prosrc => 'table_am_handler_out' },
+{ oid => '9559', descr => 'I/O',
+  proname => 'anycompatible_in', prorettype => 'anycompatible',
+  proargtypes => 'cstring', prosrc => 'anycompatible_in' },
+{ oid => '9560', descr => 'I/O',
+  proname => 'anycompatible_out', prorettype => 'cstring',
+  proargtypes => 'anycompatible', prosrc => 'anycompatible_out' },
+{ oid => '9561', descr => 'I/O',
+  proname => 'anycompatiblearray_in', prorettype => 'anycompatiblearray',
+  proargtypes => 'cstring', prosrc => 'anycompatiblearray_in' },
+{ oid => '9562', descr => 'I/O',
+  proname => 'anycompatiblearray_out', provolatile => 's',
+  prorettype => 'cstring', proargtypes => 'anycompatiblearray',
+  prosrc => 'anycompatiblearray_out' },
+{ oid => '9563', descr => 'I/O',
+  proname => 'anycompatiblearray_recv', provolatile => 's',
+  prorettype => 'anycompatiblearray', proargtypes => 'internal',
+  prosrc => 'anycompatiblearray_recv' },
+{ oid => '9564', descr => 'I/O',
+  proname => 'anycompatiblearray_send', provolatile => 's',
+  prorettype => 'bytea', proargtypes => 'anycompatiblearray',
+  prosrc => 'anycompatiblearray_send' },
+{ oid => '9565', descr => 'I/O',
+  proname => 'anycompatiblenonarray_in', prorettype => 'anycompatiblenonarray',
+  proargtypes => 'cstring', prosrc => 'anycompatiblenonarray_in' },
+{ oid => '9566', descr => 'I/O',
+  proname => 'anycompatiblenonarray_out', prorettype => 'cstring',
+  proargtypes => 'anycompatiblenonarray',
+  prosrc => 'anycompatiblenonarray_out' },
+{ oid => '9567', descr => 'I/O',
+  proname => 'anycompatiblerange_in', provolatile => 's',
+  prorettype => 'anycompatiblerange', proargtypes => 'cstring oid int4',
+  prosrc => 'anycompatiblerange_in' },
+{ oid => '9568', descr => 'I/O',
+  proname => 'anycompatiblerange_out', provolatile => 's',
+  prorettype => 'cstring', proargtypes => 'anycompatiblerange',
+  prosrc => 'anycompatiblerange_out' },
 
 # tablesample method handlers
 { oid => '3313', descr => 'BERNOULLI tablesample method handler',
@@ -7459,8 +7496,8 @@
   proname => 'regcollationrecv', prorettype => 'regcollation',
   proargtypes => 'internal', prosrc => 'regcollationrecv' },
 { oid => '4197', descr => 'I/O',
-  proname => 'regcollationsend', prorettype => 'bytea', proargtypes => 'regcollation',
-  prosrc => 'regcollationsend' },
+  proname => 'regcollationsend', prorettype => 'bytea',
+  proargtypes => 'regcollation', prosrc => 'regcollationsend' },
 { oid => '2454', descr => 'I/O',
   proname => 'regtyperecv', prorettype => 'regtype', proargtypes => 'internal',
   prosrc => 'regtyperecv' },
diff --git a/src/include/catalog/pg_type.dat b/src/include/catalog/pg_type.dat
index bb21cf166db..2e6110e3f2c 100644
--- a/src/include/catalog/pg_type.dat
+++ b/src/include/catalog/pg_type.dat
@@ -382,7 +382,8 @@
 { oid => '4191', array_type_oid => '4192', descr => 'registered collation',
   typname => 'regcollation', typlen => '4', typbyval => 't', typcategory => 'N',
   typinput => 'regcollationin', typoutput => 'regcollationout',
-  typreceive => 'regcollationrecv', typsend => 'regcollationsend', typalign => 'i' },
+  typreceive => 'regcollationrecv', typsend => 'regcollationsend',
+  typalign => 'i' },
 { oid => '2206', array_type_oid => '2211', descr => 'registered type',
   typname => 'regtype', typlen => '4', typbyval => 't', typcategory => 'N',
   typinput => 'regtypein', typoutput => 'regtypeout',
@@ -590,9 +591,34 @@
   typoutput => 'table_am_handler_out', typreceive => '-', typsend => '-',
   typalign => 'i' },
 { oid => '3831',
-  descr => 'pseudo-type representing a polymorphic base type that is a range',
+  descr => 'pseudo-type representing a range over a polymorphic base type',
   typname => 'anyrange', typlen => '-1', typbyval => 'f', typtype => 'p',
   typcategory => 'P', typinput => 'anyrange_in', typoutput => 'anyrange_out',
   typreceive => '-', typsend => '-', typalign => 'd', typstorage => 'x' },
+{ oid => '9550',
+  descr => 'pseudo-type representing a polymorphic common type',
+  typname => 'anycompatible', typlen => '4', typbyval => 't', typtype => 'p',
+  typcategory => 'P', typinput => 'anycompatible_in',
+  typoutput => 'anycompatible_out', typreceive => '-', typsend => '-',
+  typalign => 'i' },
+{ oid => '9551',
+  descr => 'pseudo-type representing an array of polymorphic common type elements',
+  typname => 'anycompatiblearray', typlen => '-1', typbyval => 'f',
+  typtype => 'p', typcategory => 'P', typinput => 'anycompatiblearray_in',
+  typoutput => 'anycompatiblearray_out',
+  typreceive => 'anycompatiblearray_recv', typsend => 'anycompatiblearray_send',
+  typalign => 'd', typstorage => 'x' },
+{ oid => '9552',
+  descr => 'pseudo-type representing a polymorphic common type that is not an array',
+  typname => 'anycompatiblenonarray', typlen => '4', typbyval => 't',
+  typtype => 'p', typcategory => 'P', typinput => 'anycompatiblenonarray_in',
+  typoutput => 'anycompatiblenonarray_out', typreceive => '-', typsend => '-',
+  typalign => 'i' },
+{ oid => '9553',
+  descr => 'pseudo-type representing a range over a polymorphic common type',
+  typname => 'anycompatiblerange', typlen => '-1', typbyval => 'f',
+  typtype => 'p', typcategory => 'P', typinput => 'anycompatiblerange_in',
+  typoutput => 'anycompatiblerange_out', typreceive => '-', typsend => '-',
+  typalign => 'd', typstorage => 'x' },
 
 ]
diff --git a/src/include/catalog/pg_type.h b/src/include/catalog/pg_type.h
index 97890946c5d..7b375626484 100644
--- a/src/include/catalog/pg_type.h
+++ b/src/include/catalog/pg_type.h
@@ -295,12 +295,23 @@ typedef FormData_pg_type *Form_pg_type;
 
 /* Is a type OID a polymorphic pseudotype?	(Beware of multiple evaluation) */
 #define IsPolymorphicType(typid)  \
+	(IsPolymorphicTypeFamily1(typid) || \
+	 IsPolymorphicTypeFamily2(typid))
+
+/* Code not part of polymorphic type resolution should not use these macros: */
+#define IsPolymorphicTypeFamily1(typid)  \
 	((typid) == ANYELEMENTOID || \
 	 (typid) == ANYARRAYOID || \
 	 (typid) == ANYNONARRAYOID || \
 	 (typid) == ANYENUMOID || \
 	 (typid) == ANYRANGEOID)
 
+#define IsPolymorphicTypeFamily2(typid)  \
+	((typid) == ANYCOMPATIBLEOID || \
+	 (typid) == ANYCOMPATIBLEARRAYOID || \
+	 (typid) == ANYCOMPATIBLENONARRAYOID || \
+	 (typid) == ANYCOMPATIBLERANGEOID)
+
 #endif							/* EXPOSE_TO_CLIENT_CODE */
 
 
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
index c8e43e684f5..828ff5a288f 100644
--- a/src/pl/plpgsql/src/pl_comp.c
+++ b/src/pl/plpgsql/src/pl_comp.c
@@ -507,11 +507,13 @@ do_compile(FunctionCallInfo fcinfo,
 			{
 				if (forValidator)
 				{
-					if (rettypeid == ANYARRAYOID)
+					if (rettypeid == ANYARRAYOID ||
+						rettypeid == ANYCOMPATIBLEARRAYOID)
 						rettypeid = INT4ARRAYOID;
-					else if (rettypeid == ANYRANGEOID)
+					else if (rettypeid == ANYRANGEOID ||
+							 rettypeid == ANYCOMPATIBLERANGEOID)
 						rettypeid = INT4RANGEOID;
-					else		/* ANYELEMENT or ANYNONARRAY */
+					else		/* ANYELEMENT or ANYNONARRAY or ANYCOMPATIBLE */
 						rettypeid = INT4OID;
 					/* XXX what could we use for ANYENUM? */
 				}
@@ -2493,12 +2495,16 @@ plpgsql_resolve_polymorphic_argtypes(int numargs,
 				case ANYELEMENTOID:
 				case ANYNONARRAYOID:
 				case ANYENUMOID:	/* XXX dubious */
+				case ANYCOMPATIBLEOID:
+				case ANYCOMPATIBLENONARRAYOID:
 					argtypes[i] = INT4OID;
 					break;
 				case ANYARRAYOID:
+				case ANYCOMPATIBLEARRAYOID:
 					argtypes[i] = INT4ARRAYOID;
 					break;
 				case ANYRANGEOID:
+				case ANYCOMPATIBLERANGEOID:
 					argtypes[i] = INT4RANGEOID;
 					break;
 				default:
diff --git a/src/test/regress/expected/aggregates.out b/src/test/regress/expected/aggregates.out
index 0073072a368..3259a22516e 100644
--- a/src/test/regress/expected/aggregates.out
+++ b/src/test/regress/expected/aggregates.out
@@ -1950,6 +1950,30 @@ select least_agg(variadic array[q1,q2]) from int8_tbl;
  -4567890123456789
 (1 row)
 
+select cleast_agg(q1,q2) from int8_tbl;
+    cleast_agg     
+-------------------
+ -4567890123456789
+(1 row)
+
+select cleast_agg(4.5,f1) from int4_tbl;
+ cleast_agg  
+-------------
+ -2147483647
+(1 row)
+
+select cleast_agg(variadic array[4.5,f1]) from int4_tbl;
+ cleast_agg  
+-------------
+ -2147483647
+(1 row)
+
+select pg_typeof(cleast_agg(variadic array[4.5,f1])) from int4_tbl;
+ pg_typeof 
+-----------
+ numeric
+(1 row)
+
 -- test aggregates with common transition functions share the same states
 begin work;
 create type avg_state as (total bigint, count bigint);
diff --git a/src/test/regress/expected/create_aggregate.out b/src/test/regress/expected/create_aggregate.out
index a2eb9996e15..dcf69094237 100644
--- a/src/test/regress/expected/create_aggregate.out
+++ b/src/test/regress/expected/create_aggregate.out
@@ -59,13 +59,39 @@ create aggregate aggfns(integer,integer,text) (
    sfunc = aggfns_trans, stype = aggtype[], sspace = 10000,
    initcond = '{}'
 );
--- variadic aggregate
+-- check error cases that would require run-time type coercion
+create function least_accum(int8, int8) returns int8 language sql as
+  'select least($1, $2)';
+create aggregate least_agg(int4) (
+  stype = int8, sfunc = least_accum
+);  -- fails
+ERROR:  function least_accum(bigint, bigint) requires run-time type coercion
+drop function least_accum(int8, int8);
+create function least_accum(anycompatible, anycompatible)
+returns anycompatible language sql as
+  'select least($1, $2)';
+create aggregate least_agg(int4) (
+  stype = int8, sfunc = least_accum
+);  -- fails
+ERROR:  function least_accum(bigint, bigint) requires run-time type coercion
+create aggregate least_agg(int8) (
+  stype = int8, sfunc = least_accum
+);
+drop function least_accum(anycompatible, anycompatible) cascade;
+NOTICE:  drop cascades to function least_agg(bigint)
+-- variadic aggregates
 create function least_accum(anyelement, variadic anyarray)
 returns anyelement language sql as
   'select least($1, min($2[i])) from generate_subscripts($2,1) g(i)';
 create aggregate least_agg(variadic items anyarray) (
   stype = anyelement, sfunc = least_accum
 );
+create function cleast_accum(anycompatible, variadic anycompatiblearray)
+returns anycompatible language sql as
+  'select least($1, min($2[i])) from generate_subscripts($2,1) g(i)';
+create aggregate cleast_agg(variadic items anycompatiblearray) (
+  stype = anycompatible, sfunc = cleast_accum
+);
 -- test ordered-set aggs using built-in support functions
 create aggregate my_percentile_disc(float8 ORDER BY anyelement) (
   stype = internal,
diff --git a/src/test/regress/expected/opr_sanity.out b/src/test/regress/expected/opr_sanity.out
index 40468e8f497..3c0b21d633e 100644
--- a/src/test/regress/expected/opr_sanity.out
+++ b/src/test/regress/expected/opr_sanity.out
@@ -329,7 +329,7 @@ SELECT p1.oid, p1.proname
 FROM pg_proc as p1
 WHERE p1.prorettype IN
     ('anyelement'::regtype, 'anyarray'::regtype, 'anynonarray'::regtype,
-     'anyenum'::regtype, 'anyrange'::regtype)
+     'anyenum'::regtype)
   AND NOT
     ('anyelement'::regtype = ANY (p1.proargtypes) OR
      'anyarray'::regtype = ANY (p1.proargtypes) OR
@@ -337,22 +337,64 @@ WHERE p1.prorettype IN
      'anyenum'::regtype = ANY (p1.proargtypes) OR
      'anyrange'::regtype = ANY (p1.proargtypes))
 ORDER BY 2;
- oid  |     proname      
-------+------------------
+ oid  |    proname     
+------+----------------
  2296 | anyarray_in
  2502 | anyarray_recv
  2312 | anyelement_in
  3504 | anyenum_in
  2777 | anynonarray_in
- 3832 | anyrange_in
   750 | array_in
  2400 | array_recv
  3506 | enum_in
  3532 | enum_recv
+(9 rows)
+
+-- anyrange is tighter than the rest, can only resolve from anyrange input
+SELECT p1.oid, p1.proname
+FROM pg_proc as p1
+WHERE p1.prorettype = 'anyrange'::regtype
+  AND NOT
+     'anyrange'::regtype = ANY (p1.proargtypes)
+ORDER BY 2;
+ oid  |     proname      
+------+------------------
+ 3832 | anyrange_in
  3876 | range_gist_union
  3834 | range_in
  3836 | range_recv
-(13 rows)
+(4 rows)
+
+-- similarly for the anycompatible family
+SELECT p1.oid, p1.proname
+FROM pg_proc as p1
+WHERE p1.prorettype IN
+    ('anycompatible'::regtype, 'anycompatiblearray'::regtype,
+     'anycompatiblenonarray'::regtype)
+  AND NOT
+    ('anycompatible'::regtype = ANY (p1.proargtypes) OR
+     'anycompatiblearray'::regtype = ANY (p1.proargtypes) OR
+     'anycompatiblenonarray'::regtype = ANY (p1.proargtypes) OR
+     'anycompatiblerange'::regtype = ANY (p1.proargtypes))
+ORDER BY 2;
+ oid  |         proname          
+------+--------------------------
+ 9559 | anycompatible_in
+ 9561 | anycompatiblearray_in
+ 9563 | anycompatiblearray_recv
+ 9565 | anycompatiblenonarray_in
+(4 rows)
+
+SELECT p1.oid, p1.proname
+FROM pg_proc as p1
+WHERE p1.prorettype = 'anycompatiblerange'::regtype
+  AND NOT
+     'anycompatiblerange'::regtype = ANY (p1.proargtypes)
+ORDER BY 2;
+ oid  |        proname        
+------+-----------------------
+ 9567 | anycompatiblerange_in
+(1 row)
 
 -- Look for functions that accept cstring and are neither datatype input
 -- functions nor encoding conversion functions.  It's almost never a good
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index dfc10e32426..d0a6b630b8f 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -1823,6 +1823,88 @@ select f1(int4range(42, 49)) as int, f1(float8range(4.5, 7.8)) as num;
 (1 row)
 
 drop function f1(x anyrange);
+create function f1(x anycompatible, y anycompatible) returns anycompatiblearray as $$
+begin
+  return array[x, y];
+end$$ language plpgsql;
+select f1(2, 4) as int, f1(2, 4.5) as num;
+  int  |   num   
+-------+---------
+ {2,4} | {2,4.5}
+(1 row)
+
+drop function f1(x anycompatible, y anycompatible);
+create function f1(x anycompatiblerange, y anycompatible, z anycompatible) returns anycompatiblearray as $$
+begin
+  return array[lower(x), upper(x), y, z];
+end$$ language plpgsql;
+select f1(int4range(42, 49), 11, 2::smallint) as int, f1(float8range(4.5, 7.8), 7.8, 11::real) as num;
+     int      |       num        
+--------------+------------------
+ {42,49,11,2} | {4.5,7.8,7.8,11}
+(1 row)
+
+select f1(int4range(42, 49), 11, 4.5) as fail;  -- range type doesn't fit
+ERROR:  function f1(int4range, integer, numeric) does not exist
+LINE 1: select f1(int4range(42, 49), 11, 4.5) as fail;
+               ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function f1(x anycompatiblerange, y anycompatible, z anycompatible);
+-- fail, can't infer type:
+create function f1(x anycompatible) returns anycompatiblerange as $$
+begin
+  return array[x + 1, x + 2];
+end$$ language plpgsql;
+ERROR:  cannot determine result data type
+DETAIL:  A result of type anycompatiblerange requires at least one input of type anycompatiblerange.
+create function f1(x anycompatiblerange, y anycompatiblearray) returns anycompatiblerange as $$
+begin
+  return x;
+end$$ language plpgsql;
+select f1(int4range(42, 49), array[11]) as int, f1(float8range(4.5, 7.8), array[7]) as num;
+   int   |    num    
+---------+-----------
+ [42,49) | [4.5,7.8)
+(1 row)
+
+drop function f1(x anycompatiblerange, y anycompatiblearray);
+create function f1(a anyelement, b anyarray,
+                   c anycompatible, d anycompatible,
+                   OUT x anyarray, OUT y anycompatiblearray)
+as $$
+begin
+  x := a || b;
+  y := array[c, d];
+end$$ language plpgsql;
+select x, pg_typeof(x), y, pg_typeof(y)
+  from f1(11, array[1, 2], 42, 34.5);
+    x     | pg_typeof |     y     | pg_typeof 
+----------+-----------+-----------+-----------
+ {11,1,2} | integer[] | {42,34.5} | numeric[]
+(1 row)
+
+select x, pg_typeof(x), y, pg_typeof(y)
+  from f1(11, array[1, 2], point(1,2), point(3,4));
+    x     | pg_typeof |         y         | pg_typeof 
+----------+-----------+-------------------+-----------
+ {11,1,2} | integer[] | {"(1,2)","(3,4)"} | point[]
+(1 row)
+
+select x, pg_typeof(x), y, pg_typeof(y)
+  from f1(11, '{1,2}', point(1,2), '(3,4)');
+    x     | pg_typeof |         y         | pg_typeof 
+----------+-----------+-------------------+-----------
+ {11,1,2} | integer[] | {"(1,2)","(3,4)"} | point[]
+(1 row)
+
+select x, pg_typeof(x), y, pg_typeof(y)
+  from f1(11, array[1, 2.2], 42, 34.5);  -- fail
+ERROR:  function f1(integer, numeric[], integer, numeric) does not exist
+LINE 2:   from f1(11, array[1, 2.2], 42, 34.5);
+               ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function f1(a anyelement, b anyarray,
+                 c anycompatible, d anycompatible);
 --
 -- Test handling of OUT parameters, including polymorphic cases.
 -- Note that RETURN is optional with OUT params; we try both ways.
@@ -1940,6 +2022,25 @@ select * from duplic('foo'::text);
 (1 row)
 
 drop function duplic(anyelement);
+create function duplic(in i anycompatiblerange, out j anycompatible, out k anycompatiblearray) as $$
+begin
+  j := lower(i);
+  k := array[lower(i),upper(i)];
+  return;
+end$$ language plpgsql;
+select * from duplic(int4range(42,49));
+ j  |    k    
+----+---------
+ 42 | {42,49}
+(1 row)
+
+select * from duplic(textrange('aaa', 'bbb'));
+  j  |     k     
+-----+-----------
+ aaa | {aaa,bbb}
+(1 row)
+
+drop function duplic(anycompatiblerange);
 --
 -- test PERFORM
 --
diff --git a/src/test/regress/expected/polymorphism.out b/src/test/regress/expected/polymorphism.out
index 331562de19d..d86a7004a6f 100644
--- a/src/test/regress/expected/polymorphism.out
+++ b/src/test/regress/expected/polymorphism.out
@@ -72,6 +72,82 @@ select polyf(int4range(42, 49)) as int, polyf(float8range(4.5, 7.8)) as num;
 (1 row)
 
 drop function polyf(x anyrange);
+create function polyf(x anycompatible, y anycompatible) returns anycompatiblearray as $$
+  select array[x, y]
+$$ language sql;
+select polyf(2, 4) as int, polyf(2, 4.5) as num;
+  int  |   num   
+-------+---------
+ {2,4} | {2,4.5}
+(1 row)
+
+drop function polyf(x anycompatible, y anycompatible);
+create function polyf(x anycompatiblerange, y anycompatible, z anycompatible) returns anycompatiblearray as $$
+  select array[lower(x), upper(x), y, z]
+$$ language sql;
+select polyf(int4range(42, 49), 11, 2::smallint) as int, polyf(float8range(4.5, 7.8), 7.8, 11::real) as num;
+     int      |       num        
+--------------+------------------
+ {42,49,11,2} | {4.5,7.8,7.8,11}
+(1 row)
+
+select polyf(int4range(42, 49), 11, 4.5) as fail;  -- range type doesn't fit
+ERROR:  function polyf(int4range, integer, numeric) does not exist
+LINE 1: select polyf(int4range(42, 49), 11, 4.5) as fail;
+               ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function polyf(x anycompatiblerange, y anycompatible, z anycompatible);
+-- fail, can't infer type:
+create function polyf(x anycompatible) returns anycompatiblerange as $$
+  select array[x + 1, x + 2]
+$$ language sql;
+ERROR:  cannot determine result data type
+DETAIL:  A result of type anycompatiblerange requires at least one input of type anycompatiblerange.
+create function polyf(x anycompatiblerange, y anycompatiblearray) returns anycompatiblerange as $$
+  select x
+$$ language sql;
+select polyf(int4range(42, 49), array[11]) as int, polyf(float8range(4.5, 7.8), array[7]) as num;
+   int   |    num    
+---------+-----------
+ [42,49) | [4.5,7.8)
+(1 row)
+
+drop function polyf(x anycompatiblerange, y anycompatiblearray);
+create function polyf(a anyelement, b anyarray,
+                      c anycompatible, d anycompatible,
+                      OUT x anyarray, OUT y anycompatiblearray)
+as $$
+  select a || b, array[c, d]
+$$ language sql;
+select x, pg_typeof(x), y, pg_typeof(y)
+  from polyf(11, array[1, 2], 42, 34.5);
+    x     | pg_typeof |     y     | pg_typeof 
+----------+-----------+-----------+-----------
+ {11,1,2} | integer[] | {42,34.5} | numeric[]
+(1 row)
+
+select x, pg_typeof(x), y, pg_typeof(y)
+  from polyf(11, array[1, 2], point(1,2), point(3,4));
+    x     | pg_typeof |         y         | pg_typeof 
+----------+-----------+-------------------+-----------
+ {11,1,2} | integer[] | {"(1,2)","(3,4)"} | point[]
+(1 row)
+
+select x, pg_typeof(x), y, pg_typeof(y)
+  from polyf(11, '{1,2}', point(1,2), '(3,4)');
+    x     | pg_typeof |         y         | pg_typeof 
+----------+-----------+-------------------+-----------
+ {11,1,2} | integer[] | {"(1,2)","(3,4)"} | point[]
+(1 row)
+
+select x, pg_typeof(x), y, pg_typeof(y)
+  from polyf(11, array[1, 2.2], 42, 34.5);  -- fail
+ERROR:  function polyf(integer, numeric[], integer, numeric) does not exist
+LINE 2:   from polyf(11, array[1, 2.2], 42, 34.5);
+               ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function polyf(a anyelement, b anyarray,
+                    c anycompatible, d anycompatible);
 --
 -- Polymorphic aggregate tests
 --
@@ -1621,3 +1697,238 @@ View definition:
 
 drop view dfview;
 drop function dfunc(anyelement, anyelement, bool);
+--
+-- Tests for ANYCOMPATIBLE polymorphism family
+--
+create function anyctest(anycompatible, anycompatible)
+returns anycompatible as $$
+  select greatest($1, $2)
+$$ language sql;
+select x, pg_typeof(x) from anyctest(11, 12) x;
+ x  | pg_typeof 
+----+-----------
+ 12 | integer
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, 12.3) x;
+  x   | pg_typeof 
+------+-----------
+ 12.3 | numeric
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, point(1,2)) x;  -- fail
+ERROR:  function anyctest(integer, point) does not exist
+LINE 1: select x, pg_typeof(x) from anyctest(11, point(1,2)) x;
+                                    ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+select x, pg_typeof(x) from anyctest('11', '12.3') x;  -- defaults to text
+  x   | pg_typeof 
+------+-----------
+ 12.3 | text
+(1 row)
+
+drop function anyctest(anycompatible, anycompatible);
+create function anyctest(anycompatible, anycompatible)
+returns anycompatiblearray as $$
+  select array[$1, $2]
+$$ language sql;
+select x, pg_typeof(x) from anyctest(11, 12) x;
+    x    | pg_typeof 
+---------+-----------
+ {11,12} | integer[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, 12.3) x;
+     x     | pg_typeof 
+-----------+-----------
+ {11,12.3} | numeric[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, array[1,2]) x;  -- fail
+ERROR:  function anyctest(integer, integer[]) does not exist
+LINE 1: select x, pg_typeof(x) from anyctest(11, array[1,2]) x;
+                                    ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function anyctest(anycompatible, anycompatible);
+create function anyctest(anycompatible, anycompatiblearray)
+returns anycompatiblearray as $$
+  select array[$1] || $2
+$$ language sql;
+select x, pg_typeof(x) from anyctest(11, array[12]) x;
+    x    | pg_typeof 
+---------+-----------
+ {11,12} | integer[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, array[12.3]) x;
+     x     | pg_typeof 
+-----------+-----------
+ {11,12.3} | numeric[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(12.3, array[13]) x;
+     x     | pg_typeof 
+-----------+-----------
+ {12.3,13} | numeric[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(12.3, '{13,14.4}') x;
+       x        | pg_typeof 
+----------------+-----------
+ {12.3,13,14.4} | numeric[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, array[point(1,2)]) x;  -- fail
+ERROR:  function anyctest(integer, point[]) does not exist
+LINE 1: select x, pg_typeof(x) from anyctest(11, array[point(1,2)]) ...
+                                    ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+select x, pg_typeof(x) from anyctest(11, 12) x;  -- fail
+ERROR:  function anyctest(integer, integer) does not exist
+LINE 1: select x, pg_typeof(x) from anyctest(11, 12) x;
+                                    ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function anyctest(anycompatible, anycompatiblearray);
+create function anyctest(anycompatible, anycompatiblerange)
+returns anycompatiblerange as $$
+  select $2
+$$ language sql;
+select x, pg_typeof(x) from anyctest(11, int4range(4,7)) x;
+   x   | pg_typeof 
+-------+-----------
+ [4,7) | int4range
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, numrange(4,7)) x;
+   x   | pg_typeof 
+-------+-----------
+ [4,7) | numrange
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, 12) x;  -- fail
+ERROR:  function anyctest(integer, integer) does not exist
+LINE 1: select x, pg_typeof(x) from anyctest(11, 12) x;
+                                    ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+select x, pg_typeof(x) from anyctest(11.2, int4range(4,7)) x;  -- fail
+ERROR:  function anyctest(numeric, int4range) does not exist
+LINE 1: select x, pg_typeof(x) from anyctest(11.2, int4range(4,7)) x...
+                                    ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+select x, pg_typeof(x) from anyctest(11.2, '[4,7)') x;  -- fail
+ERROR:  could not determine polymorphic type anycompatiblerange because input has type unknown
+drop function anyctest(anycompatible, anycompatiblerange);
+create function anyctest(anycompatiblerange, anycompatiblerange)
+returns anycompatible as $$
+  select lower($1) + upper($2)
+$$ language sql;
+select x, pg_typeof(x) from anyctest(int4range(11,12), int4range(4,7)) x;
+ x  | pg_typeof 
+----+-----------
+ 18 | integer
+(1 row)
+
+select x, pg_typeof(x) from anyctest(int4range(11,12), numrange(4,7)) x; -- fail
+ERROR:  function anyctest(int4range, numrange) does not exist
+LINE 1: select x, pg_typeof(x) from anyctest(int4range(11,12), numra...
+                                    ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function anyctest(anycompatiblerange, anycompatiblerange);
+-- fail, can't infer result type:
+create function anyctest(anycompatible)
+returns anycompatiblerange as $$
+  select $1
+$$ language sql;
+ERROR:  cannot determine result data type
+DETAIL:  A result of type anycompatiblerange requires at least one input of type anycompatiblerange.
+create function anyctest(anycompatiblenonarray, anycompatiblenonarray)
+returns anycompatiblearray as $$
+  select array[$1, $2]
+$$ language sql;
+select x, pg_typeof(x) from anyctest(11, 12) x;
+    x    | pg_typeof 
+---------+-----------
+ {11,12} | integer[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, 12.3) x;
+     x     | pg_typeof 
+-----------+-----------
+ {11,12.3} | numeric[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(array[11], array[1,2]) x;  -- fail
+ERROR:  function anyctest(integer[], integer[]) does not exist
+LINE 1: select x, pg_typeof(x) from anyctest(array[11], array[1,2]) ...
+                                    ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function anyctest(anycompatiblenonarray, anycompatiblenonarray);
+create function anyctest(a anyelement, b anyarray,
+                         c anycompatible, d anycompatible)
+returns anycompatiblearray as $$
+  select array[c, d]
+$$ language sql;
+select x, pg_typeof(x) from anyctest(11, array[1, 2], 42, 34.5) x;
+     x     | pg_typeof 
+-----------+-----------
+ {42,34.5} | numeric[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, array[1, 2], point(1,2), point(3,4)) x;
+         x         | pg_typeof 
+-------------------+-----------
+ {"(1,2)","(3,4)"} | point[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, '{1,2}', point(1,2), '(3,4)') x;
+         x         | pg_typeof 
+-------------------+-----------
+ {"(1,2)","(3,4)"} | point[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, array[1, 2.2], 42, 34.5) x;  -- fail
+ERROR:  function anyctest(integer, numeric[], integer, numeric) does not exist
+LINE 1: select x, pg_typeof(x) from anyctest(11, array[1, 2.2], 42, ...
+                                    ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function anyctest(a anyelement, b anyarray,
+                       c anycompatible, d anycompatible);
+create function anyctest(variadic anycompatiblearray)
+returns anycompatiblearray as $$
+  select $1
+$$ language sql;
+select x, pg_typeof(x) from anyctest(11, 12) x;
+    x    | pg_typeof 
+---------+-----------
+ {11,12} | integer[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, 12.2) x;
+     x     | pg_typeof 
+-----------+-----------
+ {11,12.2} | numeric[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, '12') x;
+    x    | pg_typeof 
+---------+-----------
+ {11,12} | integer[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(11, '12.2') x;  -- fail
+ERROR:  invalid input syntax for type integer: "12.2"
+LINE 1: select x, pg_typeof(x) from anyctest(11, '12.2') x;
+                                                 ^
+select x, pg_typeof(x) from anyctest(variadic array[11, 12]) x;
+    x    | pg_typeof 
+---------+-----------
+ {11,12} | integer[]
+(1 row)
+
+select x, pg_typeof(x) from anyctest(variadic array[11, 12.2]) x;
+     x     | pg_typeof 
+-----------+-----------
+ {11,12.2} | numeric[]
+(1 row)
+
+drop function anyctest(variadic anycompatiblearray);
diff --git a/src/test/regress/expected/rangefuncs.out b/src/test/regress/expected/rangefuncs.out
index cdfc43e8549..7eced284520 100644
--- a/src/test/regress/expected/rangefuncs.out
+++ b/src/test/regress/expected/rangefuncs.out
@@ -1557,6 +1557,59 @@ CREATE FUNCTION bad (f1 int, out f2 anyelement, out f3 anyarray)
 AS 'select $1, array[$1,$1]' LANGUAGE sql;
 ERROR:  cannot determine result data type
 DETAIL:  A result of type anyelement requires at least one input of type anyelement, anyarray, anynonarray, anyenum, or anyrange.
+CREATE FUNCTION dup (f1 anycompatible, f2 anycompatiblearray, f3 out anycompatible, f4 out anycompatiblearray)
+AS 'select $1, $2' LANGUAGE sql;
+SELECT dup(22, array[44]);
+    dup    
+-----------
+ (22,{44})
+(1 row)
+
+SELECT dup(4.5, array[44]);
+    dup     
+------------
+ (4.5,{44})
+(1 row)
+
+SELECT dup(22, array[44::bigint]);
+    dup    
+-----------
+ (22,{44})
+(1 row)
+
+SELECT *, pg_typeof(f3), pg_typeof(f4) FROM dup(22, array[44::bigint]);
+ f3 |  f4  | pg_typeof | pg_typeof 
+----+------+-----------+-----------
+ 22 | {44} | bigint    | bigint[]
+(1 row)
+
+DROP FUNCTION dup(f1 anycompatible, f2 anycompatiblearray);
+CREATE FUNCTION dup (f1 anycompatiblerange, f2 out anycompatible, f3 out anycompatiblearray, f4 out anycompatiblerange)
+AS 'select lower($1), array[lower($1), upper($1)], $1' LANGUAGE sql;
+SELECT dup(int4range(4,7));
+         dup         
+---------------------
+ (4,"{4,7}","[4,7)")
+(1 row)
+
+SELECT dup(numrange(4,7));
+         dup         
+---------------------
+ (4,"{4,7}","[4,7)")
+(1 row)
+
+SELECT dup(textrange('aaa', 'bbb'));
+              dup              
+-------------------------------
+ (aaa,"{aaa,bbb}","[aaa,bbb)")
+(1 row)
+
+DROP FUNCTION dup(f1 anycompatiblerange);
+-- fails, no way to deduce outputs
+CREATE FUNCTION bad (f1 anyarray, out f2 anycompatible, out f3 anycompatiblearray)
+AS 'select $1, array[$1,$1]' LANGUAGE sql;
+ERROR:  cannot determine result data type
+DETAIL:  A result of type anycompatible requires at least one input of type anycompatible, anycompatiblearray, anycompatiblenonarray, or anycompatiblerange.
 --
 -- table functions
 --
diff --git a/src/test/regress/expected/rangetypes.out b/src/test/regress/expected/rangetypes.out
index a28741a888c..c421f5394fe 100644
--- a/src/test/regress/expected/rangetypes.out
+++ b/src/test/regress/expected/rangetypes.out
@@ -1405,6 +1405,32 @@ ERROR:  function rangetypes_sql(numrange, integer[]) does not exist
 LINE 1: select rangetypes_sql(numrange(1,10), ARRAY[2,20]);
                ^
 HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+create function anycompatiblearray_anycompatiblerange_func(a anycompatiblearray, r anycompatiblerange)
+  returns anycompatible as 'select $1[1] + lower($2);' language sql;
+select anycompatiblearray_anycompatiblerange_func(ARRAY[1,2], int4range(10,20));
+ anycompatiblearray_anycompatiblerange_func 
+--------------------------------------------
+                                         11
+(1 row)
+
+select anycompatiblearray_anycompatiblerange_func(ARRAY[1,2], numrange(10,20));
+ anycompatiblearray_anycompatiblerange_func 
+--------------------------------------------
+                                         11
+(1 row)
+
+-- should fail
+select anycompatiblearray_anycompatiblerange_func(ARRAY[1.1,2], int4range(10,20));
+ERROR:  function anycompatiblearray_anycompatiblerange_func(numeric[], int4range) does not exist
+LINE 1: select anycompatiblearray_anycompatiblerange_func(ARRAY[1.1,...
+               ^
+HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
+drop function anycompatiblearray_anycompatiblerange_func(anycompatiblearray, anycompatiblerange);
+-- should fail
+create function bogus_func(anycompatible)
+  returns anycompatiblerange as 'select int4range(1,10)' language sql;
+ERROR:  cannot determine result data type
+DETAIL:  A result of type anycompatiblerange requires at least one input of type anycompatiblerange.
 --
 -- Arrays of ranges
 --
diff --git a/src/test/regress/expected/type_sanity.out b/src/test/regress/expected/type_sanity.out
index cd7fc03b04c..274130e7062 100644
--- a/src/test/regress/expected/type_sanity.out
+++ b/src/test/regress/expected/type_sanity.out
@@ -131,14 +131,16 @@ WHERE p1.typinput = p2.oid AND NOT
 
 -- Check for type of the variadic array parameter's elements.
 -- provariadic should be ANYOID if the type of the last element is ANYOID,
--- ANYELEMENTOID if the type of the last element is ANYARRAYOID, and otherwise
--- the element type corresponding to the array type.
+-- ANYELEMENTOID if the type of the last element is ANYARRAYOID,
+-- ANYCOMPATIBLEOID if the type of the last element is ANYCOMPATIBLEARRAYOID,
+-- and otherwise the element type corresponding to the array type.
 SELECT oid::regprocedure, provariadic::regtype, proargtypes::regtype[]
 FROM pg_proc
 WHERE provariadic != 0
 AND case proargtypes[array_length(proargtypes, 1)-1]
-    WHEN 2276 THEN 2276 -- any -> any
-	WHEN 2277 THEN 2283 -- anyarray -> anyelement
+	WHEN '"any"'::regtype THEN '"any"'::regtype
+	WHEN 'anyarray'::regtype THEN 'anyelement'::regtype
+	WHEN 'anycompatiblearray'::regtype THEN 'anycompatible'::regtype
 	ELSE (SELECT t.oid
 		  FROM pg_type t
 		  WHERE t.typarray = proargtypes[array_length(proargtypes, 1)-1])
diff --git a/src/test/regress/sql/aggregates.sql b/src/test/regress/sql/aggregates.sql
index 02578330a6f..5da6f4152be 100644
--- a/src/test/regress/sql/aggregates.sql
+++ b/src/test/regress/sql/aggregates.sql
@@ -740,6 +740,10 @@ drop view aggordview1;
 select least_agg(q1,q2) from int8_tbl;
 select least_agg(variadic array[q1,q2]) from int8_tbl;
 
+select cleast_agg(q1,q2) from int8_tbl;
+select cleast_agg(4.5,f1) from int4_tbl;
+select cleast_agg(variadic array[4.5,f1]) from int4_tbl;
+select pg_typeof(cleast_agg(variadic array[4.5,f1])) from int4_tbl;
 
 -- test aggregates with common transition functions share the same states
 begin work;
diff --git a/src/test/regress/sql/create_aggregate.sql b/src/test/regress/sql/create_aggregate.sql
index fd7cd400c19..d4b4036fd7d 100644
--- a/src/test/regress/sql/create_aggregate.sql
+++ b/src/test/regress/sql/create_aggregate.sql
@@ -72,7 +72,31 @@ create aggregate aggfns(integer,integer,text) (
    initcond = '{}'
 );
 
--- variadic aggregate
+-- check error cases that would require run-time type coercion
+create function least_accum(int8, int8) returns int8 language sql as
+  'select least($1, $2)';
+
+create aggregate least_agg(int4) (
+  stype = int8, sfunc = least_accum
+);  -- fails
+
+drop function least_accum(int8, int8);
+
+create function least_accum(anycompatible, anycompatible)
+returns anycompatible language sql as
+  'select least($1, $2)';
+
+create aggregate least_agg(int4) (
+  stype = int8, sfunc = least_accum
+);  -- fails
+
+create aggregate least_agg(int8) (
+  stype = int8, sfunc = least_accum
+);
+
+drop function least_accum(anycompatible, anycompatible) cascade;
+
+-- variadic aggregates
 create function least_accum(anyelement, variadic anyarray)
 returns anyelement language sql as
   'select least($1, min($2[i])) from generate_subscripts($2,1) g(i)';
@@ -81,6 +105,14 @@ create aggregate least_agg(variadic items anyarray) (
   stype = anyelement, sfunc = least_accum
 );
 
+create function cleast_accum(anycompatible, variadic anycompatiblearray)
+returns anycompatible language sql as
+  'select least($1, min($2[i])) from generate_subscripts($2,1) g(i)';
+
+create aggregate cleast_agg(variadic items anycompatiblearray) (
+  stype = anycompatible, sfunc = cleast_accum
+);
+
 -- test ordered-set aggs using built-in support functions
 create aggregate my_percentile_disc(float8 ORDER BY anyelement) (
   stype = internal,
diff --git a/src/test/regress/sql/opr_sanity.sql b/src/test/regress/sql/opr_sanity.sql
index f06f245db3b..389d5b2464a 100644
--- a/src/test/regress/sql/opr_sanity.sql
+++ b/src/test/regress/sql/opr_sanity.sql
@@ -273,7 +273,7 @@ SELECT p1.oid, p1.proname
 FROM pg_proc as p1
 WHERE p1.prorettype IN
     ('anyelement'::regtype, 'anyarray'::regtype, 'anynonarray'::regtype,
-     'anyenum'::regtype, 'anyrange'::regtype)
+     'anyenum'::regtype)
   AND NOT
     ('anyelement'::regtype = ANY (p1.proargtypes) OR
      'anyarray'::regtype = ANY (p1.proargtypes) OR
@@ -282,6 +282,37 @@ WHERE p1.prorettype IN
      'anyrange'::regtype = ANY (p1.proargtypes))
 ORDER BY 2;
 
+-- anyrange is tighter than the rest, can only resolve from anyrange input
+
+SELECT p1.oid, p1.proname
+FROM pg_proc as p1
+WHERE p1.prorettype = 'anyrange'::regtype
+  AND NOT
+     'anyrange'::regtype = ANY (p1.proargtypes)
+ORDER BY 2;
+
+-- similarly for the anycompatible family
+
+SELECT p1.oid, p1.proname
+FROM pg_proc as p1
+WHERE p1.prorettype IN
+    ('anycompatible'::regtype, 'anycompatiblearray'::regtype,
+     'anycompatiblenonarray'::regtype)
+  AND NOT
+    ('anycompatible'::regtype = ANY (p1.proargtypes) OR
+     'anycompatiblearray'::regtype = ANY (p1.proargtypes) OR
+     'anycompatiblenonarray'::regtype = ANY (p1.proargtypes) OR
+     'anycompatiblerange'::regtype = ANY (p1.proargtypes))
+ORDER BY 2;
+
+SELECT p1.oid, p1.proname
+FROM pg_proc as p1
+WHERE p1.prorettype = 'anycompatiblerange'::regtype
+  AND NOT
+     'anycompatiblerange'::regtype = ANY (p1.proargtypes)
+ORDER BY 2;
+
+
 -- Look for functions that accept cstring and are neither datatype input
 -- functions nor encoding conversion functions.  It's almost never a good
 -- idea to use cstring input for a function meant to be called from SQL;
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index c5e6e6e5ede..07c60c80e48 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -1618,6 +1618,62 @@ select f1(int4range(42, 49)) as int, f1(float8range(4.5, 7.8)) as num;
 
 drop function f1(x anyrange);
 
+create function f1(x anycompatible, y anycompatible) returns anycompatiblearray as $$
+begin
+  return array[x, y];
+end$$ language plpgsql;
+
+select f1(2, 4) as int, f1(2, 4.5) as num;
+
+drop function f1(x anycompatible, y anycompatible);
+
+create function f1(x anycompatiblerange, y anycompatible, z anycompatible) returns anycompatiblearray as $$
+begin
+  return array[lower(x), upper(x), y, z];
+end$$ language plpgsql;
+
+select f1(int4range(42, 49), 11, 2::smallint) as int, f1(float8range(4.5, 7.8), 7.8, 11::real) as num;
+
+select f1(int4range(42, 49), 11, 4.5) as fail;  -- range type doesn't fit
+
+drop function f1(x anycompatiblerange, y anycompatible, z anycompatible);
+
+-- fail, can't infer type:
+create function f1(x anycompatible) returns anycompatiblerange as $$
+begin
+  return array[x + 1, x + 2];
+end$$ language plpgsql;
+
+create function f1(x anycompatiblerange, y anycompatiblearray) returns anycompatiblerange as $$
+begin
+  return x;
+end$$ language plpgsql;
+
+select f1(int4range(42, 49), array[11]) as int, f1(float8range(4.5, 7.8), array[7]) as num;
+
+drop function f1(x anycompatiblerange, y anycompatiblearray);
+
+create function f1(a anyelement, b anyarray,
+                   c anycompatible, d anycompatible,
+                   OUT x anyarray, OUT y anycompatiblearray)
+as $$
+begin
+  x := a || b;
+  y := array[c, d];
+end$$ language plpgsql;
+
+select x, pg_typeof(x), y, pg_typeof(y)
+  from f1(11, array[1, 2], 42, 34.5);
+select x, pg_typeof(x), y, pg_typeof(y)
+  from f1(11, array[1, 2], point(1,2), point(3,4));
+select x, pg_typeof(x), y, pg_typeof(y)
+  from f1(11, '{1,2}', point(1,2), '(3,4)');
+select x, pg_typeof(x), y, pg_typeof(y)
+  from f1(11, array[1, 2.2], 42, 34.5);  -- fail
+
+drop function f1(a anyelement, b anyarray,
+                 c anycompatible, d anycompatible);
+
 --
 -- Test handling of OUT parameters, including polymorphic cases.
 -- Note that RETURN is optional with OUT params; we try both ways.
@@ -1699,6 +1755,18 @@ select * from duplic('foo'::text);
 
 drop function duplic(anyelement);
 
+create function duplic(in i anycompatiblerange, out j anycompatible, out k anycompatiblearray) as $$
+begin
+  j := lower(i);
+  k := array[lower(i),upper(i)];
+  return;
+end$$ language plpgsql;
+
+select * from duplic(int4range(42,49));
+select * from duplic(textrange('aaa', 'bbb'));
+
+drop function duplic(anycompatiblerange);
+
 --
 -- test PERFORM
 --
diff --git a/src/test/regress/sql/polymorphism.sql b/src/test/regress/sql/polymorphism.sql
index 9c7b43efebb..b57591f69f6 100644
--- a/src/test/regress/sql/polymorphism.sql
+++ b/src/test/regress/sql/polymorphism.sql
@@ -53,6 +53,56 @@ select polyf(int4range(42, 49)) as int, polyf(float8range(4.5, 7.8)) as num;
 
 drop function polyf(x anyrange);
 
+create function polyf(x anycompatible, y anycompatible) returns anycompatiblearray as $$
+  select array[x, y]
+$$ language sql;
+
+select polyf(2, 4) as int, polyf(2, 4.5) as num;
+
+drop function polyf(x anycompatible, y anycompatible);
+
+create function polyf(x anycompatiblerange, y anycompatible, z anycompatible) returns anycompatiblearray as $$
+  select array[lower(x), upper(x), y, z]
+$$ language sql;
+
+select polyf(int4range(42, 49), 11, 2::smallint) as int, polyf(float8range(4.5, 7.8), 7.8, 11::real) as num;
+
+select polyf(int4range(42, 49), 11, 4.5) as fail;  -- range type doesn't fit
+
+drop function polyf(x anycompatiblerange, y anycompatible, z anycompatible);
+
+-- fail, can't infer type:
+create function polyf(x anycompatible) returns anycompatiblerange as $$
+  select array[x + 1, x + 2]
+$$ language sql;
+
+create function polyf(x anycompatiblerange, y anycompatiblearray) returns anycompatiblerange as $$
+  select x
+$$ language sql;
+
+select polyf(int4range(42, 49), array[11]) as int, polyf(float8range(4.5, 7.8), array[7]) as num;
+
+drop function polyf(x anycompatiblerange, y anycompatiblearray);
+
+create function polyf(a anyelement, b anyarray,
+                      c anycompatible, d anycompatible,
+                      OUT x anyarray, OUT y anycompatiblearray)
+as $$
+  select a || b, array[c, d]
+$$ language sql;
+
+select x, pg_typeof(x), y, pg_typeof(y)
+  from polyf(11, array[1, 2], 42, 34.5);
+select x, pg_typeof(x), y, pg_typeof(y)
+  from polyf(11, array[1, 2], point(1,2), point(3,4));
+select x, pg_typeof(x), y, pg_typeof(y)
+  from polyf(11, '{1,2}', point(1,2), '(3,4)');
+select x, pg_typeof(x), y, pg_typeof(y)
+  from polyf(11, array[1, 2.2], 42, 34.5);  -- fail
+
+drop function polyf(a anyelement, b anyarray,
+                    c anycompatible, d anycompatible);
+
 
 --
 -- Polymorphic aggregate tests
@@ -868,3 +918,112 @@ select * from dfview;
 
 drop view dfview;
 drop function dfunc(anyelement, anyelement, bool);
+
+--
+-- Tests for ANYCOMPATIBLE polymorphism family
+--
+
+create function anyctest(anycompatible, anycompatible)
+returns anycompatible as $$
+  select greatest($1, $2)
+$$ language sql;
+
+select x, pg_typeof(x) from anyctest(11, 12) x;
+select x, pg_typeof(x) from anyctest(11, 12.3) x;
+select x, pg_typeof(x) from anyctest(11, point(1,2)) x;  -- fail
+select x, pg_typeof(x) from anyctest('11', '12.3') x;  -- defaults to text
+
+drop function anyctest(anycompatible, anycompatible);
+
+create function anyctest(anycompatible, anycompatible)
+returns anycompatiblearray as $$
+  select array[$1, $2]
+$$ language sql;
+
+select x, pg_typeof(x) from anyctest(11, 12) x;
+select x, pg_typeof(x) from anyctest(11, 12.3) x;
+select x, pg_typeof(x) from anyctest(11, array[1,2]) x;  -- fail
+
+drop function anyctest(anycompatible, anycompatible);
+
+create function anyctest(anycompatible, anycompatiblearray)
+returns anycompatiblearray as $$
+  select array[$1] || $2
+$$ language sql;
+
+select x, pg_typeof(x) from anyctest(11, array[12]) x;
+select x, pg_typeof(x) from anyctest(11, array[12.3]) x;
+select x, pg_typeof(x) from anyctest(12.3, array[13]) x;
+select x, pg_typeof(x) from anyctest(12.3, '{13,14.4}') x;
+select x, pg_typeof(x) from anyctest(11, array[point(1,2)]) x;  -- fail
+select x, pg_typeof(x) from anyctest(11, 12) x;  -- fail
+
+drop function anyctest(anycompatible, anycompatiblearray);
+
+create function anyctest(anycompatible, anycompatiblerange)
+returns anycompatiblerange as $$
+  select $2
+$$ language sql;
+
+select x, pg_typeof(x) from anyctest(11, int4range(4,7)) x;
+select x, pg_typeof(x) from anyctest(11, numrange(4,7)) x;
+select x, pg_typeof(x) from anyctest(11, 12) x;  -- fail
+select x, pg_typeof(x) from anyctest(11.2, int4range(4,7)) x;  -- fail
+select x, pg_typeof(x) from anyctest(11.2, '[4,7)') x;  -- fail
+
+drop function anyctest(anycompatible, anycompatiblerange);
+
+create function anyctest(anycompatiblerange, anycompatiblerange)
+returns anycompatible as $$
+  select lower($1) + upper($2)
+$$ language sql;
+
+select x, pg_typeof(x) from anyctest(int4range(11,12), int4range(4,7)) x;
+select x, pg_typeof(x) from anyctest(int4range(11,12), numrange(4,7)) x; -- fail
+
+drop function anyctest(anycompatiblerange, anycompatiblerange);
+
+-- fail, can't infer result type:
+create function anyctest(anycompatible)
+returns anycompatiblerange as $$
+  select $1
+$$ language sql;
+
+create function anyctest(anycompatiblenonarray, anycompatiblenonarray)
+returns anycompatiblearray as $$
+  select array[$1, $2]
+$$ language sql;
+
+select x, pg_typeof(x) from anyctest(11, 12) x;
+select x, pg_typeof(x) from anyctest(11, 12.3) x;
+select x, pg_typeof(x) from anyctest(array[11], array[1,2]) x;  -- fail
+
+drop function anyctest(anycompatiblenonarray, anycompatiblenonarray);
+
+create function anyctest(a anyelement, b anyarray,
+                         c anycompatible, d anycompatible)
+returns anycompatiblearray as $$
+  select array[c, d]
+$$ language sql;
+
+select x, pg_typeof(x) from anyctest(11, array[1, 2], 42, 34.5) x;
+select x, pg_typeof(x) from anyctest(11, array[1, 2], point(1,2), point(3,4)) x;
+select x, pg_typeof(x) from anyctest(11, '{1,2}', point(1,2), '(3,4)') x;
+select x, pg_typeof(x) from anyctest(11, array[1, 2.2], 42, 34.5) x;  -- fail
+
+drop function anyctest(a anyelement, b anyarray,
+                       c anycompatible, d anycompatible);
+
+create function anyctest(variadic anycompatiblearray)
+returns anycompatiblearray as $$
+  select $1
+$$ language sql;
+
+select x, pg_typeof(x) from anyctest(11, 12) x;
+select x, pg_typeof(x) from anyctest(11, 12.2) x;
+select x, pg_typeof(x) from anyctest(11, '12') x;
+select x, pg_typeof(x) from anyctest(11, '12.2') x;  -- fail
+select x, pg_typeof(x) from anyctest(variadic array[11, 12]) x;
+select x, pg_typeof(x) from anyctest(variadic array[11, 12.2]) x;
+
+drop function anyctest(variadic anycompatiblearray);
diff --git a/src/test/regress/sql/rangefuncs.sql b/src/test/regress/sql/rangefuncs.sql
index 476b4f27e25..ae3119a959e 100644
--- a/src/test/regress/sql/rangefuncs.sql
+++ b/src/test/regress/sql/rangefuncs.sql
@@ -407,6 +407,27 @@ DROP FUNCTION dup(anyelement);
 CREATE FUNCTION bad (f1 int, out f2 anyelement, out f3 anyarray)
 AS 'select $1, array[$1,$1]' LANGUAGE sql;
 
+CREATE FUNCTION dup (f1 anycompatible, f2 anycompatiblearray, f3 out anycompatible, f4 out anycompatiblearray)
+AS 'select $1, $2' LANGUAGE sql;
+SELECT dup(22, array[44]);
+SELECT dup(4.5, array[44]);
+SELECT dup(22, array[44::bigint]);
+SELECT *, pg_typeof(f3), pg_typeof(f4) FROM dup(22, array[44::bigint]);
+
+DROP FUNCTION dup(f1 anycompatible, f2 anycompatiblearray);
+
+CREATE FUNCTION dup (f1 anycompatiblerange, f2 out anycompatible, f3 out anycompatiblearray, f4 out anycompatiblerange)
+AS 'select lower($1), array[lower($1), upper($1)], $1' LANGUAGE sql;
+SELECT dup(int4range(4,7));
+SELECT dup(numrange(4,7));
+SELECT dup(textrange('aaa', 'bbb'));
+
+DROP FUNCTION dup(f1 anycompatiblerange);
+
+-- fails, no way to deduce outputs
+CREATE FUNCTION bad (f1 anyarray, out f2 anycompatible, out f3 anycompatiblearray)
+AS 'select $1, array[$1,$1]' LANGUAGE sql;
+
 --
 -- table functions
 --
diff --git a/src/test/regress/sql/rangetypes.sql b/src/test/regress/sql/rangetypes.sql
index 85eaa9b34c6..4048b1d1854 100644
--- a/src/test/regress/sql/rangetypes.sql
+++ b/src/test/regress/sql/rangetypes.sql
@@ -456,6 +456,22 @@ create function rangetypes_sql(q anyrange, b anyarray, out c anyelement)
 select rangetypes_sql(int4range(1,10), ARRAY[2,20]);
 select rangetypes_sql(numrange(1,10), ARRAY[2,20]);  -- match failure
 
+create function anycompatiblearray_anycompatiblerange_func(a anycompatiblearray, r anycompatiblerange)
+  returns anycompatible as 'select $1[1] + lower($2);' language sql;
+
+select anycompatiblearray_anycompatiblerange_func(ARRAY[1,2], int4range(10,20));
+
+select anycompatiblearray_anycompatiblerange_func(ARRAY[1,2], numrange(10,20));
+
+-- should fail
+select anycompatiblearray_anycompatiblerange_func(ARRAY[1.1,2], int4range(10,20));
+
+drop function anycompatiblearray_anycompatiblerange_func(anycompatiblearray, anycompatiblerange);
+
+-- should fail
+create function bogus_func(anycompatible)
+  returns anycompatiblerange as 'select int4range(1,10)' language sql;
+
 --
 -- Arrays of ranges
 --
diff --git a/src/test/regress/sql/type_sanity.sql b/src/test/regress/sql/type_sanity.sql
index fed413bf98a..4b492ce0625 100644
--- a/src/test/regress/sql/type_sanity.sql
+++ b/src/test/regress/sql/type_sanity.sql
@@ -106,15 +106,17 @@ WHERE p1.typinput = p2.oid AND NOT
 
 -- Check for type of the variadic array parameter's elements.
 -- provariadic should be ANYOID if the type of the last element is ANYOID,
--- ANYELEMENTOID if the type of the last element is ANYARRAYOID, and otherwise
--- the element type corresponding to the array type.
+-- ANYELEMENTOID if the type of the last element is ANYARRAYOID,
+-- ANYCOMPATIBLEOID if the type of the last element is ANYCOMPATIBLEARRAYOID,
+-- and otherwise the element type corresponding to the array type.
 
 SELECT oid::regprocedure, provariadic::regtype, proargtypes::regtype[]
 FROM pg_proc
 WHERE provariadic != 0
 AND case proargtypes[array_length(proargtypes, 1)-1]
-    WHEN 2276 THEN 2276 -- any -> any
-	WHEN 2277 THEN 2283 -- anyarray -> anyelement
+	WHEN '"any"'::regtype THEN '"any"'::regtype
+	WHEN 'anyarray'::regtype THEN 'anyelement'::regtype
+	WHEN 'anycompatiblearray'::regtype THEN 'anycompatible'::regtype
 	ELSE (SELECT t.oid
 		  FROM pg_type t
 		  WHERE t.typarray = proargtypes[array_length(proargtypes, 1)-1])