llvm-project/clang/test/Analysis/NewDelete-checker-test.mm

// RUN: %clang_cc1 -analyze -analyzer-checker=core,cplusplus.NewDelete -analyzer-store region -std=c++11 -fblocks -verify %s
#include "Inputs/system-header-simulator-cxx.h"
#include "Inputs/system-header-simulator-objc.h"

typedef __typeof__(sizeof(int)) size_t;
extern "C" void *malloc(size_t);
extern "C" void free(void *);
int *global;

//------------------
// check for leaks
//------------------

//----- Standard non-placement operators
void testGlobalOpNew() {
  void *p = operator new(0);
} // expected-warning{{Memory is never released; potential leak}}

void testGlobalOpNewArray() {
  void *p = operator new[](0);
} // expected-warning{{Memory is never released; potential leak}}

void testGlobalNewExpr() {
  int *p = new int;
} // expected-warning{{Memory is never released; potential leak}}

void testGlobalNewExprArray() {
  int *p = new int[0];
} // expected-warning{{Memory is never released; potential leak}}

//----- Standard nothrow placement operators
void testGlobalNoThrowPlacementOpNewBeforeOverload() {
  void *p = operator new(0, std::nothrow);
} // expected-warning{{Memory is never released; potential leak}}

void testGlobalNoThrowPlacementExprNewBeforeOverload() {
  int *p = new(std::nothrow) int;
} // expected-warning{{Memory is never released; potential leak}}


//----- Standard pointer placement operators
void testGlobalPointerPlacementNew() {
  int i;

  void *p1 = operator new(0, &i); // no warn

  void *p2 = operator new[](0, &i); // no warn

  int *p3 = new(&i) int; // no warn

  int *p4 = new(&i) int[0]; // no warn
}

//----- Other cases
void testNewMemoryIsInHeap() {
  int *p = new int;
  if (global != p) // condition is always true as 'p' wraps a heap region that 
                   // is different from a region wrapped by 'global'
    global = p; // pointer escapes
}

struct PtrWrapper {
  int *x;

  PtrWrapper(int *input) : x(input) {}
};

void testNewInvalidationPlacement(PtrWrapper *w) {
  // Ensure that we don't consider this a leak.
  new (w) PtrWrapper(new int); // no warn
}

//---------------
// other checks
//---------------

void f(int *);

void testUseAfterDelete() {
  int *p = new int;
  delete p;
  f(p); // expected-warning{{Use of memory after it is freed}}
}

void testDeleteAlloca() {
  int *p = (int *)__builtin_alloca(sizeof(int));
  delete p; // expected-warning{{Memory allocated by alloca() should not be deallocated}}
}

void testDoubleDelete() {
  int *p = new int;
  delete p;
  delete p; // expected-warning{{Attempt to free released memory}}
}

void testExprDeleteArg() {
  int i;
  delete &i; // expected-warning{{Argument to 'delete' is the address of the local variable 'i', which is not memory allocated by 'new'}}
}

void testExprDeleteArrArg() {
  int i;
  delete[] &i; // expected-warning{{Argument to 'delete[]' is the address of the local variable 'i', which is not memory allocated by 'new[]'}}
}

void testAllocDeallocNames() {
  int *p = new(std::nothrow) int[1];
  delete[] (++p); // expected-warning{{Argument to 'delete[]' is offset by 4 bytes from the start of memory allocated by 'new[]'}}
}

//----------------------------------------------------------------------------
// Check for intersections with unix.Malloc and unix.MallocWithAnnotations 
// checkers bounded with cplusplus.NewDelete.
//----------------------------------------------------------------------------

// malloc()/free() are subjects of unix.Malloc and unix.MallocWithAnnotations
void testMallocFreeNoWarn() {
  int i;
  free(&i); // no warn

  int *p1 = (int *)malloc(sizeof(int));
  free(++p1); // no warn

  int *p2 = (int *)malloc(sizeof(int));
  free(p2);
  free(p2); // no warn

  int *p3 = (int *)malloc(sizeof(int)); // no warn
}

//----- Test free standard new
void testFreeOpNew() {
  void *p = operator new(0);
  free(p);
} // expected-warning{{Memory is never released; potential leak}}
// FIXME: Pointer should escape

void testFreeNewExpr() {
  int *p = new int;
  free(p);
} // expected-warning{{Memory is never released; potential leak}}
// FIXME: Pointer should escape

void testObjcFreeNewed() {
  int *p = new int;
  NSData *nsdata = [NSData dataWithBytesNoCopy:p length:sizeof(int) freeWhenDone:1]; // expected-warning{{Memory is never released; potential leak}}
}
// FIXME: Pointer should escape

void testFreeAfterDelete() {
  int *p = new int;  
  delete p;
  free(p); // expected-warning{{Use of memory after it is freed}}
}

void testStandardPlacementNewAfterDelete() {
  int *p = new int;  
  delete p;
  p = new(p) int; // expected-warning{{Use of memory after it is freed}}
}