[llvm-bugs] [Bug 47495] New: Wsizeof-array-div false positive when divisor is sizeof reference type

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https://bugs.llvm.org/show_bug.cgi?id=47495

            Bug ID: 47495
           Summary: Wsizeof-array-div false positive when divisor is
                    sizeof reference type
           Product: clang
           Version: trunk
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P
         Component: C++
          Assignee: unassignedclangbugs at nondot.org
          Reporter: sir.venceslas at gmail.com
                CC: blitzrakete at gmail.com, dgregor at apple.com,
                    erik.pilkington at gmail.com, llvm-bugs at lists.llvm.org,
                    richard-llvm at metafoo.co.uk

Hi,

I found a bug where clang reports a false positive here:
int my_function()
{
    int array[10];

    const int narray = sizeof(array)/sizeof(int&);
    return narray;
}

clang output:
<stdin>:4:37: warning: expression does not compute the number of elements in
this array; element type is 'int', not 'int &' [-Wsizeof-array-div]
    const int narray = sizeof(array)/sizeof(int&);
                              ~~~~~ ^
<stdin>:3:9: note: array 'array' declared here
    int array[10];
        ^
<stdin>:4:37: note: place parentheses around the 'sizeof(int &)' expression to
silence this warning
    const int narray = sizeof(array)/sizeof(int&);
                                    ^
1 warning generated.

The standard says this about sizeof: "When applied to a reference or a
reference type, the result is the size of the referenced type."

I'm getting this even on the trunk version on godbolt.com
(https://godbolt.org/z/Pb4adf).

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