[BUG] poweroff command in ./u-boot -T -l causes SIG_SEGV

Hello Simon,

when running ./u-boot -T -l and issuing the poweroff command a crash occurs:

os_exit() results in std::ostream::flush() calling U-Boot's fflush with file = -138447008 (or any other negative number)

Man fflush shows the following definition:

int fflush(FILE *stream);

U-Boot's fflush() is defined as

void fflush(int file);

The pointer FILE *stream is truncated to int which may result in a negative number when invoking U-Boot's fflush() but anyway we want std::ostream::flush() to invoke glibc's fflush().

Can we ensure correct linking or do we have to rename fflush()?

Best regards

Heinrich