https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107004
Bug ID: 107004
Summary: GCC12 warning in OOB access: array subscript is partly
outside array bounds
Product: gcc
Version: 12.2.0
URL: https://godbolt.org/z/aoYh66EYb
Status: UNCONFIRMED
Keywords: TREE
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: rogerio.souza at gmail dot com
Target Milestone: ---
The code below triggers the warning:
/opt/compiler-explorer/gcc-12.2.0/include/c++/12.2.0/bits/stl_construct.h:119:7:
warning: array subscript 'int*[0]' is partly outside array bounds of 'unsigned
char [8]' [-Warray-bounds]
119 | ::new((void*)__p) _Tp(std::forward<_Args>(__args)...);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Source code:
#include <vector>
#include <cassert>
void foo(std::vector<int*>& v)
{
assert(v.size() >= 1);
v.resize(1);
}
Build command line:
g++ -std=c++20 -Wall -Wextra -pedantic -O3
Using -O2 prevents the warning, also if we use "-Wno-array-bounds". This issue
is not reproducible on GCC 11.3 or older.
Would this issue be a duplicate from
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105348?
The issue could be reproduced on Compiler Explorer:
https://godbolt.org/z/aoYh66EYb
Regards,
Rogerio
