Error check if banner is not there, as well as asprintf#5355

SiliconA-Z wants to merge 1 commit intoswiftlang:mainswiftlang/swift-corelibs-foundation:mainfrom

SiliconA-Z:error-check-in-logtostderrSiliconA-Z/swift-corelibs-foundation:error-check-in-logtostderrCopy head branch name to clipboard