test_arena.cpp


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#include "dynarray.h"

DECL_MAIN {
    // Reserving 16GiB.
    auto a = Arena(16ULL * 1024ULL * 1024ULL * 1024ULL);

    // Committing 1MiB to make space for 4 bytes (with some headroom).
    bool committed = a.Grow(4);
    assert(committed);

    a.base[0] = 'a';
    a.base[1] = 'b';
    a.base[2] = 'c';
    a.base[4] = '\0';

    std::cout << a.base << std::endl;

    // Past the declared length, but still in committed memory.
    // No segfault, but in real code it's probably a bug.
    a.base[5] = 'x';
    a.base[kBytesPerCommit-1] = 'y';

    // Reserved, but not committed memory. Segfault.
    // a.base[kBytesPerCommit] = 'x';

    return 0;
}