https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111738
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Resolution|--- |INVALID Status|UNCONFIRMED |RESOLVED --- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> --- ================================================================= ==1==ERROR: AddressSanitizer: global-buffer-overflow on address 0x0000004043e0 at pc 0x0000004012a3 bp 0x7ffd3315e4b0 sp 0x7ffd3315e4a8 WRITE of size 8 at 0x0000004043e0 thread T0 #0 0x4012a2 in i (/app/output.s+0x4012a2) (BuildId: 4eb338bebafc71b3519003fd1b76487cfb8fb27b) #1 0x4011c3 in h (/app/output.s+0x4011c3) (BuildId: 4eb338bebafc71b3519003fd1b76487cfb8fb27b) #2 0x40146f in main (/app/output.s+0x40146f) (BuildId: 4eb338bebafc71b3519003fd1b76487cfb8fb27b) #3 0x7f28b75e2082 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x24082) (BuildId: 1878e6b475720c7c51969e69ab2d276fae6d1dee) #4 0x4010fd in _start (/app/output.s+0x4010fd) (BuildId: 4eb338bebafc71b3519003fd1b76487cfb8fb27b) 0x0000004043e4 is located 0 bytes after global variable 'b' defined in '/app/example.cpp:1:8' (0x4043e0) of size 4 SUMMARY: AddressSanitizer: global-buffer-overflow (/app/output.s+0x4012a2) (BuildId: 4eb338bebafc71b3519003fd1b76487cfb8fb27b) in i Shadow bytes around the buggy address: 0x000000404100: 00 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 00 00 00 00 0x000000404180: 00 00 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 f9 f9 0x000000404200: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 0x000000404280: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 0x000000404300: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 =>0x000000404380: f9 f9 f9 f9 f9 f9 f9 f9 00 00 00 00[04]f9 f9 f9 0x000000404400: f9 f9 f9 f9 04 f9 f9 f9 f9 f9 f9 f9 04 f9 f9 f9 0x000000404480: f9 f9 f9 f9 04 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 0x000000404500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x000000404580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x000000404600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb ==1==ABORTING In this case: ``` **c = &b; ``` ... int **k = &b; *k = &j; *g |= **c; ``` Basically once I fixed the size issue (or use -m32) there is profile difference.