What is the effect of a failure to press for a ruling on the voluntariness of a confession?

Furthermore, appellant did not obtain a ruling on the voluntariness of his confession. The trial court's ruling was limited to the Miranda issue: "It was not a custodial interrogation. [] So my ruling is that there was no Miranda violation." Appellant did not ask the court to rule on whether his confession was voluntary. "Failure to press for a ruling on a motion to exclude evidence forfeits appellate review of the claim because such failure deprives the trial court of the opportunity to correct potential error in the first instance. [Citation.]" (People v. Lewis (2008) 43 Cal.4th 415, 481, disapproved on other grounds in People v. Black (2014) 58 Cal.4th 912, 919-920 & fn. 3; see also People v. Ramos (1997) 15 Cal.4th 1133, 1171.)