A C programme, as far as I can tell, does not use stack nor heap unless you explicitly put stuff there. The heap is only used if there is an explicit call to malloc/etc within the code you write/link to. It appears that no matter how simple, though, a Rust program always calls malloc and affiliated around nine times. Even the Hello World program makes some malloc calls. See for yourself :

Memory usage summary: heap total: 3404, heap peak: 1616, stack peak: 1072
         total calls   total memory   failed calls
 malloc|          6           3188              0
realloc|          2             64              0  (nomove:0, dec:0, free:0)
 calloc|          1            152              0
   free|          8           2860
Histogram for block sizes:
    0-15              1  11% =========================
   32-47              2  22% ==================================================
  112-127             1  11% =========================
  144-159             1  11% =========================
  464-479             1  11% =========================
  544-559             1  11% =========================
 1024-1039            2  22% ==================================================

This is the output memusage generates when it checks the hello world program as in its simplest implementation. I get it that computers are fast and leaks are memory safe but... seriously ? What is that ? Does linking to the standard library force you to have at least one memory leak no matter how cautious you are ? Calls to malloc and friends aren't the fastest and I don't see why the rust startup routine uses so much memory and does so many allocations where a C program can do the exact same without that overhead. Anyone knows why this choice was made ?

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