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#include <iostream>
#include <vector>
 
void f(const std::vector<int> &Cc) {
  for (auto Ii = Cc.begin(), Ee = Ii + 20; Ii != Ee; ++Ii) {
    std::cout << *Ii << std::endl;
  }
}

Compliant Solution (std::vector)

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#include <algorithm>
#include <vector>

void f(const std::vector<int> &Cc) {
  const std::vector<int>::size_type MaxSizemaxSize = 20;
  for (auto Ii = Cc.begin(), Ee = Ii + std::min(MaxSizemaxSize, Cc.size()); Ii != Ee; ++Ii) {
    // ...
  }
}

This compliant solution also uses a named constant value in compliance with DCL06-CPP. Use meaningful symbolic constants to represent literal values in program logic.

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#include <cstddef>
 
void f(const char *buf, std::size_t len) {
  // Check for overflow
  if (buf + len < buf) {
    len = -(std::size_t)buf - 1;
  }
}

This code resembles the test for wraparound from the sprint() function as implemented for the Plan 9 operating system. If buf + len < buf evaluates to true, len is assigned the remaining space minus one byte. However, because the expression buf + len < buf constitutes undefined behavior, compilers can assume this condition will never occur and optimize away the entire conditional statement.

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#include <cstdint>
 
void f(const char *buf, std::size_t len) {
  // Check for overflow
  auto bint = reinterpret_cast<std::uintptr_t>(buf);
  if (bint + len < bint) {
    len = -(std::size_t)bint - 1;
  }
}

This compliant solution works on architectures that provide a linear address space. Some word-oriented machines are likely to produce a word address with the high-order bits used as a byte selector, in which case this solution will fail. Consequently, this solution is not portable.

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