clang/test/Analysis/new-ctor-null-throw.cpp

   1 // RUN: %clang_analyze_cc1 -std=c++14 -analyzer-checker=core \
   2 // RUN:  -analyzer-config suppress-null-return-paths=false \
   3 // RUN:  -verify %s
   4 // RUN: %clang_analyze_cc1 -std=c++14 -analyzer-checker=core \
   5 // RUN:  -DSUPPRESSED \
   6 // RUN:  -verify %s
   7
   8 void clang_analyzer_eval(bool);
   9
  10 typedef __typeof__(sizeof(int)) size_t;
  11
  12
  13 // These are ill-formed. One cannot return nullptr from a throwing version of an
  14 // operator new.
  15 void *operator new(size_t size) {
  16   return nullptr;
  17   // expected-warning@-1 {{'operator new' should not return a null pointer unless it is declared 'throw()' or 'noexcept'}}
  18   // expected-warning@-2 {{null returned from function that requires a non-null return value}}
  19 }
  20 void *operator new[](size_t size) {
  21   return nullptr;
  22   // expected-warning@-1 {{'operator new[]' should not return a null pointer unless it is declared 'throw()' or 'noexcept'}}
  23   // expected-warning@-2 {{null returned from function that requires a non-null return value}}
  24 }
  25
  26 struct S {
  27   int x;
  28   S() : x(1) {}
  29   ~S() {}
  30   int getX() const { return x; }
  31 };
  32
  33 void testArrays() {
  34   S *s = new S[10]; // no-crash
  35   s[0].x = 2;
  36 #ifndef SUPPRESSED
  37   // expected-warning@-2 {{Dereference of null pointer}}
  38 #endif
  39 }
  40
  41 void testCtor() {
  42   S *s = new S();
  43   s->x = 13;
  44 #ifndef SUPPRESSED
  45   // expected-warning@-2 {{Access to field 'x' results in a dereference of a null pointer (loaded from variable 's')}}
  46 #endif
  47 }
  48
  49 void testMethod() {
  50   S *s = new S();
  51   const int X = s->getX();
  52 #ifndef SUPPRESSED
  53   // expected-warning@-2 {{Called C++ object pointer is null}}
  54 #endif
  55 }
  56