charconst-3.c

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/* Copyright (C) 2001 Free Software Foundation, Inc.  */

/* { dg-do run } */
/* { dg-options -Wno-multichar } */

/* This tests values and signedness of multichar charconsts.

   Neil Booth, 5 May 2002.  */

#include <limits.h>

int main ()
{
  /* These tests require at least 2-byte ints.  8-)  */
#if INT_MAX > 127
  int scale = (int) (unsigned char) -1 + 1;

  if ('ab' != (int) ((unsigned char) 'a' * scale + (unsigned char) 'b'))
    abort ();

  if ('\234b' != (int) ((unsigned char) '\234' * scale + (unsigned char) 'b'))
    abort ();

  if ('b\234' != (int) ((unsigned char) 'b' * scale + (unsigned char) '\234'))
    abort ();
  /* Multichar charconsts have type int and should be signed.  */
#if INT_MAX == 32767
# if '\234a' > 0
#  error Preprocessor charconsts 1
# endif
  if ('\234a' > 0)
    abort ();
#elif INT_MAX == 2147483647
# if '\234aaa' > 0
#  error Preprocessor charconsts 2
# endif
  if ('\234aaa' > 0)
    abort ();
#elif INT_MAX == 9223372036854775807
# if '\234aaaaaaa' > 0
#  error Preprocessor charconsts 3
# endif
  if ('\234aaaaaaa' > 0)
    abort ();
#endif
#endif
  return 0;
}