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A comment on Performance of Rust Language [pdf]. Parent comment

Re:Performance of Rust Language [pdf] by guerby on Tuesday May 26, 2026 @10:28AM (#48280323)
On https://godbolt.org/ select Ada and compiler option "-O2"

    function Square(num : Integer) return Integer is
        tab : array (0..100) of integer;
    begin
        for i in 0..101 loop 
            tab(i):=i; 
        end loop;
        return tab(100);
    end Square;
The assembly code generated is :

    sub     rsp, 8    #,
    mov     esi, 11   #,
    mov     edi, OFFSET FLAT:.LC0     #,
    call    "__gnat_rcheck_CE_Index_Check"  #
Loop is not run and exeption handler is called directly.

Link : https://godbolt.org/z/qT4TsKPxz

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Re:Performance of Rust Language [pdf] by Animats on Tuesday May 26, 2026 @02:42PM (#48283995)
Right, that's the extreme case, where the problem is detected at compile time. Unfortunately, it's not a user-visible error message at compile time.

Need to try an example where the size isn't known until run time.

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