[Bug c++/99185] asan initialization-order-fiasco false positive
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99185
--- Comment #7 from kal.conley at dectris dot com ---
There is no fiasco here because the default constructor of `A` does no dynamic
initialization. If the definition of `A` is changed to:
struct A {
int value;
};
then the error goes away. However, in both cases there is the same
implicitly-defined default constructor generated by the compiler. Explicitly
declaring `A() = default` should not change anything in this regard. Generating
an error in this case is not useful.
[Bug c++/99185] asan initialization-order-fiasco false positive
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99185 --- Comment #5 from kal.conley at dectris dot com --- I don't think this has anything to do with C++20. The behavior doesn't change when compiling for C++17. In any case, `g` should be static initialized with zeros and no dynamic initialization in `a.cc` should take place.
[Bug c++/99185] asan initialization-order-fiasco false positive
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99185
--- Comment #3 from kal.conley at dectris dot com ---
I don't think there should be any dynamic initialization of A here. Also, its
weird that if the definition if A is changed to:
struct A {
int value = 0;
A() = default;
};
then the error goes away.
[Bug c++/99185] asan initialization-order-fiasco false positive
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99185 --- Comment #1 from kal.conley at dectris dot com --- Strict init-order checking is enabled.
[Bug c++/99185] New: asan initialization-order-fiasco false positive
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99185
Bug ID: 99185
Summary: asan initialization-order-fiasco false positive
Product: gcc
Version: 10.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: kal.conley at dectris dot com
Target Milestone: ---
The default constructor does not initialize primitive types.
a.cc:
=
struct A {
int value;
A() = default;
};
A g;
b.cc:
=
struct A {
int value;
A() = default;
};
extern A g;
int b = []() {
g.value = 1;
return 0;
}();
int main() {
return 0;
}
$ g++ -fsanitize=address -std=c++20 a.cc b.cc; ./a.out
=
==3844820==ERROR: AddressSanitizer: initialization-order-fiasco on address
0x00404160 at pc 0x004013c6 bp 0x7fff2371ecc0 sp 0x7fff2371ecb0
WRITE of size 4 at 0x00404160 thread T0
#0 0x4013c5 in b::{lambda()#1}::operator()() const
(/home/kal/work/cxx/a.out+0x4013c5)
#1 0x4012a8 in __static_initialization_and_destruction_0(int, int)
(/home/kal/work/cxx/a.out+0x4012a8)
#2 0x40134b in _GLOBAL__sub_I_b (/home/kal/work/cxx/a.out+0x40134b)
#3 0x40142c in __libc_csu_init (/home/kal/work/cxx/a.out+0x40142c)
#4 0x7f43cfb8b00d in __libc_start_main (/lib64/libc.so.6+0x2700d)
#5 0x4010dd in _start (/home/kal/work/cxx/a.out+0x4010dd)
0x00404160 is located 0 bytes inside of global variable 'g' defined in
'a.cc:5:3' (0x404160) of size 4
registered at:
#0 0x7f43d00b5cc8 (/lib64/libasan.so.6+0x37cc8)
#1 0x401202 in _sub_I_00099_1 (/home/kal/work/cxx/a.out+0x401202)
#2 0x40142c in __libc_csu_init (/home/kal/work/cxx/a.out+0x40142c)
SUMMARY: AddressSanitizer: initialization-order-fiasco
(/home/kal/work/cxx/a.out+0x4013c5) in b::{lambda()#1}::operator()() const
Shadow bytes around the buggy address:
0x800787d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x800787e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x800787f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x80078800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x80078810: 00 00 00 00 f9 f9 f9 f9 f9 f9 f9 f9 00 00 00 00
=>0x80078820: f9 f9 f9 f9 f9 f9 f9 f9 00 00 00 00[f6]f6 f6 f6
0x80078830: f6 f6 f6 f6 00 00 00 00 04 f9 f9 f9 f9 f9 f9 f9
0x80078840: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x80078850: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x80078860: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x80078870: 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
Shadow gap: cc
==3844820==ABORTING
[Bug tree-optimization/94335] False positive -Wstringop-overflow warning with -O2
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94335
kal.conley at dectris dot com changed:
What|Removed |Added
CC||kal.conley at dectris dot com
--- Comment #6 from kal.conley at dectris dot com ---
We are hitting this warning too with:
#include
#include
int main() {
std::vector inputs(2);
std::vector outputs{inputs.begin(), inputs.end()};
outputs.back() = 1;
return 0;
}
Regards,
Kal
