gcc/testsuite/gcc.dg/uninit-38.c

   1 /* Verify that dereferencing uninitialized VLAs correctly reflects
   2    offsets into the objects.
   3    The test's main purpose is to exercise the formatting of MEM_REFs.
   4    If -Wuninitialized gets smarter and detects uninitialized accesses
   5    before they're turned into MEM_REFs the test will likely need to
   6    be adjusted.  Ditto if -Wuninitialized output changes for some
   7    other reason.
   8    { dg-do compile { target { { lp64 || ilp32 } || llp64 } } }
   9    { dg-options "-O2 -Wall -ftrack-macro-expansion=0 -fno-ipa-modref" }
  10    { dg-require-effective-target alloca } */
  11
  12 #define CONCAT(x, y)   x ## y
  13 #define CAT(x, y)      CONCAT(x, y)
  14 #define UNIQ(name)     CAT (name, __LINE__)
  15
  16 typedef __SIZE_TYPE__ size_t;
  17
  18 extern void* malloc (size_t);
  19
  20 void sink (void*, ...);
  21
  22 #define T(Type, idx, off)                       \
  23   __attribute__ ((noipa))                       \
  24   void UNIQ (test_)(int n)                      \
  25   {                                             \
  26     char a[n], *p = a;                          \
  27     Type *q = (Type*)((char*)p + off);          \
  28     sink (p, q[idx]);                           \
  29   }                                             \
  30   typedef void dummy_type
  31
  32 T (int, 0, 0);      // { dg-warning "'\\*\\(int \\*\\)a' is used uninitialized" }
  33 T (int, 0, 1);      // { dg-warning "'\\*\\(int \\*\\)\\(\\(char \\*\\)a \\+ 1\\)'" }
  34 T (int, 0, 2);      // { dg-warning "'\\*\\(int \\*\\)\\(\\(char \\*\\)a \\+ 2\\)'" }
  35 T (int, 0, 3);      // { dg-warning "'\\*\\(int \\*\\)\\(\\(char \\*\\)a \\+ 3\\)'" }
  36 T (int, 0, 4);      // { dg-warning "'\\(\\(int \\*\\)a\\)\\\[1]'" }
  37 T (int, 0, 5);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 1\\)\\)\\\[1]'" }
  38 T (int, 0, 6);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 2\\)\\)\\\[1]'" }
  39 T (int, 0, 7);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 3\\)\\)\\\[1]'" }
  40 T (int, 0, 8);      // { dg-warning "'\\(\\(int \\*\\)a\\)\\\[2]'" }
  41 T (int, 0, 9);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 1\\)\\)\\\[2]'" }
  42
  43
  44 T (int, 1, 0);      // { dg-warning "'\\(\\(int \\*\\)a\\)\\\[1]' is used uninitialized" }
  45 T (int, 1, 1);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 1\\)\\)\\\[1]'" }
  46 T (int, 1, 2);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 2\\)\\)\\\[1]'" }
  47 T (int, 1, 3);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 3\\)\\)\\\[1]'" }
  48 T (int, 1, 4);      // { dg-warning "'\\(\\(int \\*\\)a\\)\\\[2]'" }
  49 T (int, 1, 5);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 1\\)\\)\\\[2]'" }
  50 T (int, 1, 6);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 2\\)\\)\\\[2]'" }
  51 T (int, 1, 7);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 3\\)\\)\\\[2]'" }
  52 T (int, 1, 8);      // { dg-warning "'\\(\\(int \\*\\)a\\)\\\[3]'" }
  53 T (int, 1, 9);      // { dg-warning "'\\(\\(int \\*\\)\\(\\(char \\*\\)a \\+ 1\\)\\)\\\[3]'" }