modernc.org/ccgo/v3@v3.16.14/lib/testdata/gcc-9.1.0/gcc/testsuite/gcc.c-torture/execute/builtins/abs-1-lib.c (about)

     1  extern void abort (void);
     2  extern int abs_called;
     3  extern int inside_main;
     4  
     5  /* The labs call should have been optimized, but the abs call
     6     shouldn't have been.  */
     7  
     8  int
     9  abs (int x)
    10  {
    11    if (inside_main)
    12      abs_called = 1;
    13    return (x < 0 ? -x : x);
    14  }
    15  
    16  long
    17  labs (long x)
    18  {
    19    if (inside_main)
    20      abort ();
    21    return (x < 0 ? -x : x);
    22  }