https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64715
--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> --- Of course the question is whether int main (void) { struct A { char buf1[9]; char buf2[1]; } a; char *p = a.buf1; p += 4; strcpy (p, str1 + 5); } should detect a buffer overflow - because that's what the original testcase boils down to. GCC 4.9 doesn't detect a buffer overflow here - a bug? What is "the closest surrounding object" 'p' points to? What is an "object" in C terms? (what is it in C++ terms?) I start to believe the testcase is ill-formed and should have used &a.buf1[4] instead which works fine with GCC 5.