gcc/testsuite/gcc.dg/warn-sprintf-no-nul.c

   1 /* PR tree-optimization/86552 - missing warning for reading past the end
   2    of non-string arrays
   3    Exercise non-string detection in sprintf.
   4    { dg-do compile }
   5    { dg-options "-O2 -Wno-array-bounds -Wall -ftrack-macro-expansion=0" } */
   6
   7 #include "range.h"
   8
   9 typedef __WCHAR_TYPE__ wchar_t;
  10
  11 extern int sprintf (char*, const char*, ...);
  12
  13 extern char *dst;
  14
  15 int i0 = 0;
  16 int i1 = 1;
  17
  18 void sink (int, ...);
  19
  20 #define CONCAT(a, b)   a ## b
  21 #define CAT(a, b)      CONCAT(a, b)
  22
  23 #define T(fmt, ...)                             \
  24   sink (sprintf (dst, fmt, __VA_ARGS__))
  25
  26 const char a[5] = "12345";    /* { dg-message "declared here" } */
  27 const char b[6] = "123456";   /* { dg-message "declared here" } */
  28 const char a2[][3] = {
  29   "", "1", "12", "123", "123\000"   /* { dg-warning "initializer-string for array of chars is too long" } */
  30 };
  31
  32
  33 void test_narrow (void)
  34 {
  35   /* Verify that precision suppresses the warning when it's less
  36      than the size of the array.  */
  37   T ("%.0s%.1s%.2s%.3s%.4s%.5s", a, a, a, a, a, a);
  38
  39   T ("%s", a);          /* { dg-warning ".%s. directive argument is not a nul-terminated string" } */
  40   T ("%.6s", a);        /* { dg-warning ".%.6s. directive argument is not a nul-terminated string" } */
  41
  42   /* Exercise conditional expressions involving strings and non-strings.  */
  43   const char *s0 = i0 < 0 ? a2[0] : a2[3];
  44   T ("%s", s0);         /* { dg-warning ".%s. directive argument is not a nul-terminated string" } */
  45   s0 = i0 < 0 ? "123456" : a2[4];
  46   T ("%s", s0);         /* { dg-warning ".%s. directive argument is not a nul-terminated string" } */
  47
  48   const char *s1 = i0 < 0 ? a2[3] : a2[0];
  49   T ("%s", s1);         /* { dg-warning ".%s. directive argument is not a nul-terminated string" } */
  50
  51   const char *s2 = i0 < 0 ? a2[3] : a2[4];
  52   T ("%s", s2);         /* { dg-warning ".%s. directive argument is not a nul-terminated string" } */
  53
  54   s0 = i0 < 0 ? a : b;
  55   T ("%.5s", s0);
  56
  57   /* Verify that the warning triggers even if precision prevents
  58      reading past the end of one of the non-terminated arrays but
  59      not the other.  */
  60   T ("%.6s", s0);       /* { dg-warning ".%.6s. directive argument is not a nul-terminated string" } */
  61
  62   s0 = i0 < 0 ? b : a;
  63   T ("%.7s", s0);       /* { dg-warning ".%.7s. directive argument is not a nul-terminated string" } */
  64
  65   /* Verify that at -Wformat-overflow=1 the lower bound of precision
  66      given by a range is used to determine whether or not to warn.  */
  67   int r = SR (4, 5);
  68
  69   T ("%.*s", r, a);
  70   T ("%.*s", r, b);
  71
  72   r = SR (5, 6);
  73   T ("%.*s", r, a);
  74   T ("%.*s", r, b);
  75
  76   r = SR (6, 7);
  77   T ("%.*s", r, a);     /* { dg-warning ".%.\\\*s. directive argument is not a nul-terminated string" } */
  78   T ("%.*s", r, b);
  79 }
  80
  81
  82 const wchar_t wa[5] = L"12345";   /* { dg-message "declared here" } */
  83
  84 void test_wide (void)
  85 {
  86   T ("%.0ls%.1ls%.2ls%.3ls%.4ls%.5ls", wa, wa, wa, wa, wa, wa);
  87
  88   T ("%ls", wa);        /* { dg-warning ".%ls. directive argument is not a nul-terminated string" } */
  89   T ("%.6ls", wa);      /* { dg-warning ".%.6ls. directive argument is not a nul-terminated string" } */
  90 }