gcc/testsuite/gcc.dg/Wsign-conversion.c

   1 /* Test for diagnostics for implicit conversions between signed and
   2    unsigned integer types.
   3    These tests come from gcc/testsuite/gcc.dg/overflow-warn-2.c  */
   4
   5 /* { dg-do compile } */
   6 /* { dg-options "-std=c99 -fsigned-char -Wsign-conversion" } */
   7 #include <limits.h>
   8
   9 void fsc (signed char sc);
  10 void fuc (unsigned char uc);
  11 unsigned fui (unsigned int  ui);
  12 void fsi (signed int ui);
  13
  14 void h (int x)
  15 {
  16   unsigned int ui = 3;
  17   int   si = 3;
  18   unsigned char uc = 3;
  19   signed char   sc = 3;
  20
  21   uc = ui;
  22   uc = si;
  23   sc = ui;
  24   sc = si;
  25   fuc (ui);
  26   fuc (si);
  27   fsc (ui);
  28   fsc (si);
  29
  30   fsi (si);
  31   fui (ui);
  32   fsi (uc);
  33   si = uc;
  34   fui (uc);
  35   ui = uc;
  36   fui ('A');
  37   ui = 'A';
  38   fsi ('A');
  39   si = 'A';
  40   fuc ('A');
  41   uc = 'A';
  42
  43   uc = x ? 1U : -1; /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes value from .-1. to .\[0-9\]+." } */
  44   uc = x ? SCHAR_MIN : 1U;  /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes value from .-\[0-9\]+. to .\[0-9\]+." } */
  45   uc = x ? 1 : -1; /* { dg-warning "unsigned conversion from .int. to .unsigned char. changes the value of .-1." } */
  46   uc = x ? SCHAR_MIN : 1; /* { dg-warning "unsigned conversion from .int. to .unsigned char. changes the value of .-\[0-9\]+." } */
  47   ui = x ? 1U : -1; /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes value from .-1. to .\[0-9\]+." } */
  48   ui = x ? INT_MIN : 1U; /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes value from .-\[0-9\]+. to .\[0-9\]+." } */
  49   ui = ui ? SCHAR_MIN : 1U; /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes value " } */
  50   ui = 1U * -1; /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes value " } */
  51   ui = ui + INT_MIN; /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes value " } */
  52   ui = x ? 1 : -1; /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes the value of .-1." } */
  53   ui = ui ? SCHAR_MIN : 1; /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes the value of " } */
  54
  55   fuc (-1); /* { dg-warning "unsigned conversion" } */
  56   uc = -1;  /* { dg-warning "unsigned conversion" } */
  57   fui (-1); /* { dg-warning "unsigned conversion" } */
  58   ui = -1; /* { dg-warning "unsigned conversion" } */
  59   fuc ('\xa0'); /* { dg-warning "unsigned conversion" } */
  60   uc = '\xa0'; /* { dg-warning "unsigned conversion" } */
  61   fui ('\xa0');/* { dg-warning "unsigned conversion" } */
  62   ui = '\xa0'; /* { dg-warning "unsigned conversion" } */
  63   fsi (0x80000000); /* { dg-warning "signed conversion" } */
  64   si = 0x80000000;  /* { dg-warning "signed conversion" } */
  65
  66
  67   fsi (UINT_MAX - 1);  /* { dg-warning "conversion" } */
  68   si = UINT_MAX - 1;   /* { dg-warning "conversion" } */
  69   fsi (UINT_MAX - 1U); /* { dg-warning "conversion" } */
  70   si = UINT_MAX - 1U;  /* { dg-warning "conversion" } */
  71   fsi (UINT_MAX/3U);
  72   si = UINT_MAX/3U;
  73   fsi (UINT_MAX/3);
  74   si = UINT_MAX/3;
  75   fui (UINT_MAX - 1);
  76   ui = UINT_MAX - 1;
  77
  78   uc = (unsigned char) -1;
  79   ui = -1 * (1 * -1);
  80   ui = (unsigned) -1;
  81
  82   fsc (uc); /* { dg-warning "conversion" } */
  83   sc = uc;  /* { dg-warning "conversion" } */
  84   fuc (sc); /* { dg-warning "conversion" } */
  85   uc = sc;  /* { dg-warning "conversion" } */
  86   fsi (ui); /* { dg-warning "conversion" } */
  87   si = ui;  /* { dg-warning "conversion" } */
  88   fui (si); /* { dg-warning "conversion" } */
  89   ui = si;  /* { dg-warning "conversion" } */
  90   fui (sc); /* { dg-warning "conversion" } */
  91   ui = sc;  /* { dg-warning "conversion" } */
  92 }
  93
  94 unsigned fui (unsigned a) { return a + -1; } /* { dg-warning "unsigned conversion from .int. to .unsigned int. changes value" } */
  95
  96