gcc/testsuite/gcc.dg/tree-ssa/user-printf-warn-1.c

   1 /* PR middle-end/87041 - -Wformat "reading through null pointer" on
   2    unreachable code
   3    Test to verify that the applicable subset of -Wformat-overflow warnings
   4    are issued for user-defined function declared attribute format printf.
   5    { dg-do compile }
   6    { dg-options "-O -Wformat -Wformat-overflow=1 -ftrack-macro-expansion=0" }
   7    { dg-require-effective-target int32plus } */
   8
   9 /* When debugging, define LINE to the line number of the test case to exercise
  10    and avoid exercising any of the others.  The buffer and objsize macros
  11    below make use of LINE to avoid warnings for other lines.  */
  12 #ifndef LINE
  13 # define LINE 0
  14 #endif
  15
  16 #define INT_MAX __INT_MAX__
  17 #define ATTR(...) __attribute__ ((__VA_ARGS__))
  18
  19 typedef __SIZE_TYPE__ size_t;
  20
  21 #if !__cplusplus
  22 typedef __WCHAR_TYPE__ wchar_t;
  23 #endif
  24
  25 typedef __WINT_TYPE__ wint_t;
  26
  27 ATTR (format (printf, 2, 3)) void
  28 user_print (char*, const char*, ...);
  29
  30 ATTR (format (printf, 2, 3), nonnull) void
  31 user_print_nonnull (char*, const char*, ...);
  32
  33 ATTR (format (printf, 2, 3), nonnull (2)) void
  34 user_print_nonnull_fmt (char*, const char*, ...);
  35
  36 ATTR (format (printf, 2, 4), nonnull (3)) void
  37 user_print_nonnull_other (char*, const char*, char*, ...);
  38
  39 void dummy_print (char*, const char*, ...);
  40
  41 const char chr_no_nul = 'a';
  42 const char arr_no_nul[] = { 'a', 'b' };
  43
  44
  45 /* Helper to expand function to either __builtin_f or dummy_f to
  46    make debugging GCC easy.  */
  47 #define T(...)                                                  \
  48   (((!LINE || LINE == __LINE__)                                 \
  49     ? user_print : dummy_print) (0, __VA_ARGS__))
  50
  51 /* Exercise the "%c" directive with constant arguments.  */
  52
  53 void test_user_print_format_string (void)
  54 {
  55   char *null = 0;
  56   /* Verify that no warning is issued for a null format string unless
  57      the corresponding parameter is declared nonnull.  */
  58   user_print (0, null);
  59   user_print_nonnull ("x", "y");
  60   user_print_nonnull ("x", null);   /* { dg-warning "\\\[-Wnonnull]" } */
  61   user_print_nonnull_fmt (null, "x");
  62   user_print_nonnull_fmt (0, null); /* { dg-warning "\\\[-Wnonnull]" } */
  63   user_print_nonnull_other (null, "x", "y");
  64   user_print_nonnull_other (null, "x", null);  /* { dg-warning "\\\[-Wnonnull]" } */
  65 }
  66
  67
  68 /* Exercise the "%c" directive with constant arguments.  */
  69
  70 void test_user_print_c_const (int width)
  71 {
  72   /* Verify that a warning is issued for exceeding INT_MAX bytes and
  73      not otherwise.  */
  74   T ("%*c",  INT_MAX - 1, '1');
  75   T ("%*c",  INT_MAX,     '1');
  76   T ("X%*c", INT_MAX - 1, '1');
  77   T ("X%*c", INT_MAX,     '1');   /* { dg-warning "directive output of \[0-9\]+ bytes causes result to exceed .INT_MAX." } */
  78
  79   T ("%*c%*c", INT_MAX - 1, '1', INT_MAX - 1, '2'); /* { dg-warning "directive output of \[0-9\]+ bytes causes result to exceed .INT_MAX." } */
  80
  81   T ("%*cX", INT_MAX - 2, '1');
  82   T ("%*cX", INT_MAX - 1, '1');
  83   T ("%*cX", INT_MAX,     '1');   /* { dg-warning "output of \[0-9\]+ bytes causes result to exceed .INT_MAX." } */
  84
  85   if (width < INT_MAX - 1)
  86     width = INT_MAX - 1;
  87   T ("%*cX", width, '1');
  88   T ("%*cXY", width, '1');        /* { dg-warning ".XY. directive output of 2 bytes causes result to exceed .INT_MAX." } */
  89
  90   /* Also exercise a non-constant format string.  The warning points
  91      to the line where the format is declared (see bug 87773) so avoid
  92      triggering that bug here.  */
  93   const char *fmt = "%*cXYZ";  T (fmt, width, '1');            /* { dg-warning ".XYZ. directive output of 3 bytes causes result to exceed .INT_MAX." } */
  94 }
  95
  96
  97 /* Exercise the "%s" directive with constant arguments.  */
  98
  99 void test_user_print_s_const (int width)
 100 {
 101   const char *null = 0;
 102
 103   T ("%s", null);                 /* { dg-warning ".%s. directive argument is null" } */
 104   T ("%.0s", null);               /* { dg-warning ".%.0s. directive argument is null" } */
 105
 106   /* Verify no warning is issued for unreachable code.  */
 107   if (null)
 108     T ("%s", null);
 109
 110   T ("%s", &chr_no_nul);          /* { dg-warning ".%s. directive argument is not a nul-terminated string" } */
 111   T ("%s", arr_no_nul);           /* { dg-warning ".%s. directive argument is not a nul-terminated string" } */
 112
 113   /* Verify that output in excess of INT_MAX bytes is diagnosed even
 114      when the size of the destination object is unknown.  */
 115   T ("%*s",  INT_MAX - 1, "");
 116   T ("%*s",  INT_MAX,     "");
 117   T ("X%*s", INT_MAX,     "");    /* { dg-warning "directive output of \[0-9\]+ bytes causes result to exceed .INT_MAX." } */
 118
 119   if (width < INT_MAX - 1)
 120     width = INT_MAX - 1;
 121   T ("%*sX", width, "1");
 122   T ("%*sXY", width, "1");        /* { dg-warning ".XY. directive output of 2 bytes causes result to exceed .INT_MAX." } */
 123 }
 124
 125
 126 const wchar_t wchr_no_nul = L'a';
 127 const wchar_t warr_no_nul[] = { L'a', L'b' };
 128
 129 /* Exercise the "%s" directive with constant arguments.  */
 130
 131 void test_user_print_ls_const (int width)
 132 {
 133   const wchar_t *null = 0;
 134
 135   T ("%ls", null);                /* { dg-warning ".%ls. directive argument is null" } */
 136   T ("%.0ls", null);              /* { dg-warning ".%.0ls. directive argument is null" } */
 137
 138   /* Verify no warning is issued for unreachable code.  */
 139   if (null)
 140     T ("%ls", null);
 141
 142   T ("%ls", &wchr_no_nul);        /* { dg-warning ".%ls. directive argument is not a nul-terminated string" } */
 143   T ("%ls", warr_no_nul);         /* { dg-warning ".%ls. directive argument is not a nul-terminated string" "pr88211" { xfail *-*-* } } */
 144
 145   /* Verify that output in excess of INT_MAX bytes is diagnosed even
 146      when the size of the destination object is unknown.  */
 147   T ("%*ls",  INT_MAX - 1, L"");
 148   T ("%*ls",  INT_MAX,     L"");
 149   T ("X%*ls", INT_MAX,     L"");  /* { dg-warning "directive output of \[0-9\]+ bytes causes result to exceed .INT_MAX." } */
 150
 151   if (width < INT_MAX - 1)
 152     width = INT_MAX - 1;
 153   T ("%*lsX", width, L"1");
 154   T ("%*lsXY", width, L"1");      /* { dg-warning ".XY. directive output of 2 bytes causes result to exceed .INT_MAX." } */
 155 }