llvm/clang-tools-extra/test/clang-tidy/checkers/bugprone/multi-level-implicit-pointer-conversion.cpp

// RUN: %check_clang_tidy %s bugprone-multi-level-implicit-pointer-conversion %t

using OneStar = void*;
using OneStarFancy = OneStar;

void takeFirstLevelVoidPtr(OneStar message);
void takeFirstLevelConstVoidPtr(const OneStarFancy message);
void takeFirstLevelConstVoidPtrConst(const void* const message);
void takeSecondLevelVoidPtr(void** message);

void** getSecondLevelVoidPtr();
void* getFirstLevelVoidPtr();
int** getSecondLevelIntPtr();
int* getFirstLevelIntPtr();

int table[5];

void test()
{
  void** secondLevelVoidPtr;
  int* firstLevelIntPtr;

  // CHECK-MESSAGES: :[[@LINE+1]]:13: warning: multilevel pointer conversion from 'void **' to 'void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  void* a = getSecondLevelVoidPtr();

  void** b = getSecondLevelVoidPtr();
  void* c = getFirstLevelVoidPtr();

  // CHECK-MESSAGES: :[[@LINE+1]]:13: warning: multilevel pointer conversion from 'int **' to 'void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  void* d = getSecondLevelIntPtr();

  takeFirstLevelVoidPtr(&table);

  takeFirstLevelVoidPtr(firstLevelIntPtr);

  takeFirstLevelVoidPtr(getFirstLevelIntPtr());

  // CHECK-MESSAGES: :[[@LINE+1]]:25: warning: multilevel pointer conversion from 'void **' to 'void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  takeFirstLevelVoidPtr(secondLevelVoidPtr);

  // CHECK-MESSAGES: :[[@LINE+1]]:30: warning: multilevel pointer conversion from 'void **' to 'void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  takeFirstLevelConstVoidPtr(secondLevelVoidPtr);

  // CHECK-MESSAGES: :[[@LINE+1]]:35: warning: multilevel pointer conversion from 'void **' to 'const void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  takeFirstLevelConstVoidPtrConst(secondLevelVoidPtr);

  // CHECK-MESSAGES: :[[@LINE+1]]:35: warning: multilevel pointer conversion from 'void ***' to 'const void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  takeFirstLevelConstVoidPtrConst(&secondLevelVoidPtr);

  takeSecondLevelVoidPtr(secondLevelVoidPtr);

  // CHECK-MESSAGES: :[[@LINE+1]]:25: warning: multilevel pointer conversion from 'void **' to 'void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  takeFirstLevelVoidPtr(getSecondLevelVoidPtr());

  // CHECK-MESSAGES: :[[@LINE+1]]:30: warning: multilevel pointer conversion from 'void **' to 'void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  takeFirstLevelConstVoidPtr(getSecondLevelVoidPtr());

  // CHECK-MESSAGES: :[[@LINE+1]]:35: warning: multilevel pointer conversion from 'void **' to 'const void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  takeFirstLevelConstVoidPtrConst(getSecondLevelVoidPtr());

  // CHECK-MESSAGES: :[[@LINE+1]]:25: warning: multilevel pointer conversion from 'int **' to 'void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
  takeFirstLevelVoidPtr(getSecondLevelIntPtr());

  takeSecondLevelVoidPtr(getSecondLevelVoidPtr());
}

namespace PR93959 {
  void free(void*);

  void test() {
    char **p = nullptr;
    free(p);
    // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: multilevel pointer conversion from 'char **' to 'void *', please use explicit cast [bugprone-multi-level-implicit-pointer-conversion]
    free((void *)p);
    free(static_cast<void *>(p));
  }
}