False negative: out-of-bounds write through pointer arithmetic

[Rodri]

Hi, I found a false negative regarding the rule arrayIndexOutOfBounds.

Cppcheck misses an out-of-bounds write when array indexing is written as pointer arithmetic.

int a[2];

void f() {
  *(a + 2) = 0;
}

Actual result

Cppcheck does not report arrayIndexOutOfBounds. Replacing *(a + 2) = 0 with a[2] = 0 produces the warning.

Expected result

Cppcheck should report the out-of-bounds write in both forms.

Verification

The issue was reproduced with:

cppcheck --output-format=xmlv2 --enable=all array_pointer.cpp

Version: 2.21.0

[CHR]

See https://trac.cppcheck.net/ticket/10201