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From: "vanyacpp at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug sanitizer/99418] sanitizer checks for accessing
 multidimentional VLA-array
Date: Sat, 06 Mar 2021 22:53:05 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D99418

--- Comment #1 from Ivan Sorokin <vanyacpp at gmail dot com> ---
Here is the reduced example. It doesn't SIGSEGV, but it doesn't report any
sanitizer errors either:

$ g++ -g -fsanitize=3Dbounds 3.cpp
$ cat 3.cpp
#include <cstddef>

void escape(int& a)
{}

void test(size_t n, size_t m)
{
    int mas[n][m];
    escape(mas[n - 1][m]);
}

int main()
{
    test(4, 3);
}

Surprisingly if I replace taking a reference with writing to the array it w=
ill
show an error.=