On 2014/10/11 11:26, Eric Blake wrote: > On 10/10/2014 09:21 PM, Gonglei wrote: > >> >> Actually, I had noted that C standard says it is a no-operation. >> But that doesn't mean that every C-library handles it like that. > > EVERY libc that is C89 compliant handles it like that. The last > platform that failed on free(NULL) was SunOS 4, which is such > museum-ware it's not funny. There is no need to cater to platforms from > 25 years ago. >
OK.Thanks for explanation! >> Some people saw crashes for free(NULL), so it's best to avoid >> calling the free in the first place (caller) or using g_free() in >> qemu_vfree(). > > Absolutely not. g_free is unsafe to use except for pointers from > g_malloc, which is NOT the case that qemu_vfree is used on. > Got it, thanks :) But why some callers make a check, but some other callers don't do this check? Can I consider those check is superfluous? -Best regards, -Gonglei
