[BP 7.6.3] Compilation error: Could not infer type for variable error for valid query

SELECT (

  SELECT c1.field1

  FROM collection1 AS c1

  WHERE c1.id IN c3.items

  UNION ALL

  SELECT c2.field2

  FROM collection2 c2 )

FROM collection3 AS c3

org.apache.asterix.common.exceptions.CompilationException: ASX1079: Compilation error: Could not infer type for variable '$$69'. (in line 2, at column 3)

    at org.apache.asterix.optimizer.rules.SetClosedRecordConstructorsRule$SettingClosedRecordVisitor.visitVariableReferenceExpression(SetClosedRecordConstructorsRule.java:175) ~[classes/:?]

    at org.apache.asterix.optimizer.rules.SetClosedRecordConstructorsRule$SettingClosedRecordVisitor.visitVariableReferenceExpression(SetClosedRecordConstructorsRule.java:80) ~[classes/:?]

    at org.apache.hyracks.algebricks.core.algebra.expressions.VariableReferenceExpression.accept(VariableReferenceExpression.java:99) ~[classes/:?]

    at org.apache.asterix.optimizer.rules.SetClosedRecordConstructorsRule$SettingClosedRecordVisitor.visitFunctionCallExpression(SetClosedRecordConstructorsRule.java:155) ~[classes/:?]

    at org.apache.asterix.optimizer.rules.SetClosedRecordConstructorsRule$SettingClosedRecordVisitor.visitFunctionCallExpression(SetClosedRecordConstructorsRule.java:80) ~[classes/:?]

    at org.apache.hyracks.algebricks.core.algebra.visitors.AbstractConstVarFunVisitor.visitScalarFunctionCallExpression(AbstractConstVarFunVisitor.java:39) ~[classes/:?]

    at org.apache.hyracks.algebricks.core.algebra.expressions.ScalarFunctionCallExpression.accept(ScalarFunctionCallExpression.java:57) ~[classes/:?]

    at org.apache.asterix.optimizer.rules.SetClosedRecordConstructorsRule$SettingClosedRecordVisitor.transform(SetClosedRecordConstructorsRule.java:94) ~[classes/:?]

    at org.apache.hyracks.algebricks.core.algebra.operators.logical.AbstractBinaryJoinOperator.acceptExpressionTransform(AbstractBinaryJoinOperator.java:74) ~[classes/:?]

    at org.apache.asterix.optimizer.rules.SetClosedRecordConstructorsRule.rewritePost(SetClosedRecordConstructorsRule.java:73) ~[classes/:?]