cppScope errorMedium

Unexpected segfault when accessing string data

Time: 0:00

BugFind the bug and fix the code

What it should do

Create a greeting message by appending a name to a base message. Example: createGreetingString("John") -> "Hello, John!"

What happens instead

Segmentation fault (core dumped)

const char* createGreetingString(const std::string& name) {
  std::string message = "Hello, " + name + "!";
  return message.c_str();
}

int main() {
  const char* greeting = createGreetingString("Alice");
  std::cout << greeting << std::endl;
  return 0;
}

Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).

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This bug belongs to the scope and closure bugs pattern

Every callback reports the last value, a counter never increments, UnboundLocalError on a variable you can see.

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const char* createGreetingString(const std::string& name) { std::string message = "Hello, " + name + "!"; return message.c_str(); } int main() { const char* greeting = createGreetingString("Alice"); std::cout << greeting << std::endl; return 0; }

Unexpected segfault when accessing string data

What it should do

What happens instead

More scope and closure bugs to practise

Unexpected segfault when accessing string data

What it should do

What happens instead

More scope and closure bugs to practise