varattrs.h

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#ifndef varattrs_h
#define varattrs_h

#include "compiler-tests.h"

/*
 * Attributes to apply to variables, using various compiler-specific
 * extensions.
 */

#if __has_attribute(unused) \
    || TCPSLICE_IS_AT_LEAST_GNUC_VERSION(2,0)
  /*
   * Compiler with support for __attribute__((unused)), or GCC 2.0 and
   * later, so it supports __attribute__((unused)).
   */
  #define _U_ __attribute__((unused))
#else
  /*
   * We don't know of any way to mark a variable as unused.
   */
  #define _U_
#endif

#endif