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1 // RUN: %clang_cc1 -analyze -analyzer-checker=unix.MallocSizeof -verify %s
2 
3 #include <stddef.h>
4 
5 void *malloc(size_t size);
6 void *calloc(size_t nmemb, size_t size);
7 void *realloc(void *ptr, size_t size);
8 void free(void *ptr);
9 
10 struct A {};
11 struct B {};
12 
foo(unsigned int unsignedInt,unsigned int readSize)13 void foo(unsigned int unsignedInt, unsigned int readSize) {
14   int *ip1 = malloc(sizeof(1));
15   int *ip2 = malloc(4 * sizeof(int));
16 
17   long *lp1 = malloc(sizeof(short)); // expected-warning {{Result of 'malloc' is converted to a pointer of type 'long', which is incompatible with sizeof operand type 'short'}}
18   long *lp2 = malloc(5 * sizeof(double)); // expected-warning {{Result of 'malloc' is converted to a pointer of type 'long', which is incompatible with sizeof operand type 'double'}}
19   char *cp3 = malloc(5 * sizeof(char) + 2); // no warning
20   unsigned char *buf = malloc(readSize + sizeof(unsignedInt)); // no warning
21 
22   struct A *ap1 = calloc(1, sizeof(struct A));
23   struct A *ap2 = calloc(2, sizeof(*ap1));
24   struct A *ap3 = calloc(2, sizeof(ap1)); // expected-warning {{Result of 'calloc' is converted to a pointer of type 'struct A', which is incompatible with sizeof operand type 'struct A *'}}
25   struct A *ap4 = calloc(3, sizeof(struct A*)); // expected-warning {{Result of 'calloc' is converted to a pointer of type 'struct A', which is incompatible with sizeof operand type 'struct A *'}}
26   struct A *ap5 = calloc(4, sizeof(struct B)); // expected-warning {{Result of 'calloc' is converted to a pointer of type 'struct A', which is incompatible with sizeof operand type 'struct B'}}
27   struct A *ap6 = realloc(ap5, sizeof(struct A));
28   struct A *ap7 = realloc(ap5, sizeof(struct B)); // expected-warning {{Result of 'realloc' is converted to a pointer of type 'struct A', which is incompatible with sizeof operand type 'struct B'}}
29 }
30 
31 // Don't warn when the types differ only by constness.
ignore_const()32 void ignore_const() {
33   const char **x = (const char **)malloc(1 * sizeof(char *)); // no-warning
34   const char ***y = (const char ***)malloc(1 * sizeof(char *)); // expected-warning {{Result of 'malloc' is converted to a pointer of type 'const char **', which is incompatible with sizeof operand type 'char *'}}
35   free(x);
36 }
37 
mallocArraySize()38 int *mallocArraySize() {
39   static const int sTable[10];
40   static const int nestedTable[10][2];
41   int *table = malloc(sizeof sTable);
42   int *table1 = malloc(sizeof nestedTable);
43   int (*table2)[2] = malloc(sizeof nestedTable);
44   int (*table3)[10][2] = malloc(sizeof nestedTable);
45   return table;
46 }
47 
mallocWrongArraySize()48 int *mallocWrongArraySize() {
49   static const double sTable[10];
50   int *table = malloc(sizeof sTable); // expected-warning {{Result of 'malloc' is converted to a pointer of type 'int', which is incompatible with sizeof operand type 'const double [10]'}}
51   return table;
52 }
53