compiler.h

   1 /* public domain */
   2
   3 #ifndef COMPILER_H
   4 #define COMPILER_H
   5
   6 #include "config-host.h"
   7
   8 /*----------------------------------------------------------------------------
   9 | The macro QEMU_GNUC_PREREQ tests for minimum version of the GNU C compiler.
  10 | The code is a copy of SOFTFLOAT_GNUC_PREREQ, see softfloat-macros.h.
  11 *----------------------------------------------------------------------------*/
  12 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
  13 # define QEMU_GNUC_PREREQ(maj, min) \
  14          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
  15 #else
  16 # define QEMU_GNUC_PREREQ(maj, min) 0
  17 #endif
  18
  19 #define QEMU_NORETURN __attribute__ ((__noreturn__))
  20
  21 #if QEMU_GNUC_PREREQ(3, 4)
  22 #define QEMU_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
  23 #else
  24 #define QEMU_WARN_UNUSED_RESULT
  25 #endif
  26
  27 #if defined(_WIN32)
  28 # define QEMU_PACKED __attribute__((gcc_struct, packed))
  29 #else
  30 # define QEMU_PACKED __attribute__((packed))
  31 #endif
  32
  33 #define cat(x,y) x ## y
  34 #define cat2(x,y) cat(x,y)
  35 #define QEMU_BUILD_BUG_ON(x) \
  36     typedef char cat2(qemu_build_bug_on__,__LINE__)[(x)?-1:1];
  37
  38 #if defined __GNUC__
  39 # if !QEMU_GNUC_PREREQ(4, 4)
  40    /* gcc versions before 4.4.x don't support gnu_printf, so use printf. */
  41 #  define GCC_ATTR __attribute__((__unused__, format(printf, 1, 2)))
  42 #  define GCC_FMT_ATTR(n, m) __attribute__((format(printf, n, m)))
  43 # else
  44    /* Use gnu_printf when supported (qemu uses standard format strings). */
  45 #  define GCC_ATTR __attribute__((__unused__, format(gnu_printf, 1, 2)))
  46 #  define GCC_FMT_ATTR(n, m) __attribute__((format(gnu_printf, n, m)))
  47 #  if defined(_WIN32)
  48     /* Map __printf__ to __gnu_printf__ because we want standard format strings
  49      * even when MinGW or GLib include files use __printf__. */
  50 #   define __printf__ __gnu_printf__
  51 #  endif
  52 # endif
  53 # if defined(__APPLE__)
  54 #  define QEMU_WEAK_ALIAS(newname, oldname) \
  55         static typeof(oldname) weak_##newname __attribute__((unused, weakref(#oldname)))
  56 #  define QEMU_WEAK_REF(newname, oldname) (weak_##newname ? weak_##newname : oldname)
  57 # else
  58 #  define QEMU_WEAK_ALIAS(newname, oldname) \
  59         typeof(oldname) newname __attribute__((weak, alias (#oldname)))
  60 #  define QEMU_WEAK_REF(newname, oldname) newname
  61 # endif
  62 #else
  63 #define GCC_ATTR /**/
  64 #define GCC_FMT_ATTR(n, m)
  65 #define QEMU_WEAK_ALIAS(newname, oldname) \
  66         _Pragma("weak " #newname "=" #oldname)
  67 #endif
  68
  69 #endif /* COMPILER_H */