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/* { dg-do run } */

/* { dg-options "-O1 -fno-tree-vrp -fwrapv" } */

/* PR tree-optimization/22236

    Avoid conversion of (signed char) {(uchar)1, +, (uchar)1}_x when

    it is not possible to prove that the scev does not wrap.

    In this PR, a sequence 1, 2, ..., 255 has to be converted to

    signed char, but this would wrap: 1, 2, ..., 127, -128, ...  The

    result should not be a linear scev {(schar)1, +, (schar)1}_x.

    The conversion should be kept: (schar) {(uchar)1, +, (uchar)1}_x.

 */

void abort(void);

static inline void

foo (signed char a)

{

  int b = a - 0x7F;

  if (b > 1)

    abort();

}

int main()

{

  unsigned char b;

  for(b = 0; b < 0xFF; b++)

    foo (b);

  return 0;

}