https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81079
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution|--- |INVALID
--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
(In reply to d25fe0be@ from comment #0)
> When object files (compiled separately) are linked together using GCC, even
> if -static-libxsan is specifed, the corresponding libraries seems not to be
> linked, resulting in undefined references to __ubsan_xxx / ... .
>
> It seems that -static-libxsan is suppressed by the absence of -fsanitize=xxx.
>
> lsan seems not to suffer from this though.
>
Hi.
It's documented pretty well:
```
-static-libasan
When the -fsanitize=address option is used to link a program, the GCC driver
automatically links against libasan. If libasan is available as a shared
library, and the -static option is not used, then this links against the shared
version of libasan. The -static-libasan option directs the GCC driver to link
libasan statically, without necessarily linking other libraries statically.
```
Thus one needs to use -fsanitize=x in linking. I also verified and liblsan
behaves the same. Problem is that liblasan does not contain a symbol that will
cause an unresolved symbol. But:
$ cat pr81079.cpp
#include <stdlib.h>
const int &f() {
return {};
}
int main() {
int *a = (int*)malloc (123);
f();
}
$ g++ pr81079.cpp -std=c++11 -c -fsanitize=leak
$ g++ pr81079.o -std=c++11 && ./a.out
[no output]
while:
$ g++ pr81079.o -std=c++11 -fsanitize=leak && ./a.out
=================================================================
==7875==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 123 byte(s) in 1 object(s) allocated from:
#0 0x2aeb4c5d15a6 in malloc (/usr/lib64/liblsan.so.0+0xd5a6)
#1 0x40062a in main (/home/marxin/Programming/testcases/a.out+0x40062a)
#2 0x2aeb4dd39469 in __libc_start_main (/lib64/libc.so.6+0x20469)
SUMMARY: LeakSanitizer: 123 byte(s) leaked in 1 allocation(s).
That said, I'm closing that as invalid.
