https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107752
Bug ID: 107752
Summary: Lack of offset information in AddressSanitizer reports
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: sanitizer
Assignee: unassigned at gcc dot gnu.org
Reporter: shaohua.li at inf dot ethz.ch
CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
jakub at gcc dot gnu.org, kcc at gcc dot gnu.org, marxin at
gcc dot gnu.org
Target Milestone: ---
Hi,
I found that GCC's ASAN reports do not include offset information, while
Clang's ASAN does. Both GCC's UBSan and Clang'UBSan include offset information.
For example, for the following code,
% cat a.c
int main() {
int a[1] = {0};
return a[1];
}
%
GCC's ASAN report only includes the line numbers of the stack trace (a.c:3):
```
=================================================================
==1842608==ERROR: AddressSanitizer: stack-buffer-overflow on address
0x7fff7181ea14 at pc 0x55f5214542e2 bp 0x7fff7181e9e0 sp 0x7fff7181e9d0
READ of size 4 at 0x7fff7181ea14 thread T0
#0 0x55f5214542e1 in main /home/shaoli/tmp/a.c:3
...
```
Clang's ASAN report includes both the line numbers and offsets of the stack
trace (a.c:3:10):
```
=================================================================
==1910102==ERROR: AddressSanitizer: stack-buffer-overflow on address
0x7ffd53e4fa64 at pc 0x55a977f71884 bp 0x7ffd53e4fa30 sp 0x7ffd53e4fa28
READ of size 4 at 0x7ffd53e4fa64 thread T0
#0 0x55a977f71883 in main /home/shaoli/tmp/a.c:3:10
```
Both GCC's and Clang's UBsans include all information:
```
a.c:3:11: runtime error: index 1 out of bounds for type 'int [1]'
a.c:3:11: runtime error: load of address 0x7ffd420a6538 with insufficient space
for an object of type 'int'
```
I believe it would be nice to include the offset information as it is very
useful for users to quickly locate bugs in their code.
