http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55940
--- Comment #7 from Frank Mehnert <fm3 at os dot inf.tu-dresden.de> 2013-01-15 15:37:43 UTC --- Actually this looks like some mixup in the generated machine code: VBoxHost_RTR0MemObjGetPagePhysAddr(): c1b: 8b 0f mov (%edi),%ecx c1d: 8b 47 04 mov 0x4(%edi),%eax c20: 8d 91 00 10 00 00 lea 0x1000(%ecx),%edx c26: 81 fa ff 1f 00 00 cmp $0x1fff,%edx c2c: 76 49 jbe c77 <VBoxHost_RTR0MemObjGetPagePhysAddr+0x5c> c2e: 81 39 10 12 61 19 cmpl $0x19611210,(%ecx) c34: 75 41 jne c77 <VBoxHost_RTR0MemObjGetPagePhysAddr+0x5c> c36: 55 push %ebp c37: 89 e5 mov %esp,%ebp c39: 57 push %edi c3a: 53 push %ebx c3b: 8b 51 08 mov 0x8(%ecx),%edx c3e: 8d 7d 08 lea 0x8(%ebp),%edi c41: 8d 5a ff lea -0x1(%edx),%ebx c44: 83 fb 07 cmp $0x7,%ebx c47: 77 34 ja c7d <VBoxHost_RTR0MemObjGetPagePhysAddr+0x62> The EDI register is loaded from stack later and the two lines at 0xc1b and 0xc1d just access the EDI register before it is properly initialized.
