---
id: cpp-errors
title: "C++ Errors"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["compile-time vs runtime errors", "dangling pointer", "C++ 에러"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.85
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["cpp", "programming-language", "w3schools", "errors"]
raw_sources: ["https://www.w3schools.com/cpp/cpp_errors.asp"]
applied_in: []
github_commit: ""
---

# [[CPP Errors]]

## 🎯 한 줄 통찰 (One-line insight)
The three runtime error examples (divide-by-zero, out-of-bounds array access, using DELETED memory via a dangling pointer) all share the same trait as C's equivalent chapter — none are caught at compile time, all three compile cleanly and only misbehave when actually executed — but C++'s third example specifically involves `new`/`delete` (`int* ptr = new int(10); delete ptr; cout << *ptr;`), a "dangling pointer" scenario that has no direct C equivalent since C's version used plain `malloc`/`free`. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Compile-time errors** — prevent compilation entirely; e.g. missing semicolon, undeclared variable, type mismatch (`invalid conversion from 'const char*' to 'int'`). [S1]
- **Runtime errors** — the program compiles but crashes/misbehaves when RUN; e.g. division by zero, out-of-bounds array access, dangling pointer (reading memory after `delete`). [S1]
- **Dangling pointer** — a pointer that still holds an address after that memory was `delete`d; dereferencing it (`*ptr`) is invalid, C++-specific terminology tied to `new`/`delete`. [S1]
- **Good habits** — initialize variables, use meaningful names, keep indentation clean, keep functions short/focused, verify loop/condition behavior, read error messages carefully. [S1]

## 📖 세부 내용 (Details)
- Type mismatch error message (more specific than C's generic phrasing): `int x = "Hello"; // error: invalid conversion from 'const char*' to 'int'`. [S1]
- Dangling pointer, a C++-specific runtime error: `int* ptr = new int(10); delete ptr; cout << *ptr; // invalid — dereferencing freed memory`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- **댕글링 포인터는 new/delete와 결합된 C++ 특유의 표현**: C의 use-after-free 예제가 malloc/free 기반이었다면, C++에서는 new/delete와 결합된 "댕글링 포인터"라는 구체적 용어로 동일한 문제가 재확인됨. [S1]

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — 컴파일 타임 에러 3종과 런타임 에러 3종을 나란히 대비시킨 것이 두 에러 범주의 근본적 차이를 이해하는 실전 학습 자료로 활용된다. [S1]

## 💻 코드 패턴 (Code patterns)
Using memory after it's been deleted — a dangling pointer, compiles fine but is invalid at runtime (C++):
```cpp
int* ptr = new int(10);
delete ptr;
cout << *ptr;  // invalid — dangling pointer
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.85
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[C++ Tutorial]]
- **관련 개념:** [[CPP Date]], [[CPP Memory Management New]], [[CPP Exceptions]]
- **참조 맥락:** 에러 섹션 첫 챕터 — 예외 처리(Exceptions) 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — C++ Errors — https://www.w3schools.com/cpp/cpp_errors.asp

## 📝 변경 이력 (Change history)
- 2026-07-04: Initial draft synthesized from the W3Schools "C++ Errors" page (Astra wiki-curation, P-Reinforce v3.1 format).
