include/qemu/compiler.h

   1 /* public domain */
   2
   3 #ifndef COMPILER_H
   4 #define COMPILER_H
   5
   6 #if defined __clang_analyzer__ || defined __COVERITY__
   7 #define QEMU_STATIC_ANALYSIS 1
   8 #endif
   9
  10 /*----------------------------------------------------------------------------
  11 | The macro QEMU_GNUC_PREREQ tests for minimum version of the GNU C compiler.
  12 | The code is a copy of SOFTFLOAT_GNUC_PREREQ, see softfloat-macros.h.
  13 *----------------------------------------------------------------------------*/
  14 #if defined(__GNUC__) && defined(__GNUC_MINOR__)
  15 # define QEMU_GNUC_PREREQ(maj, min) \
  16          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
  17 #else
  18 # define QEMU_GNUC_PREREQ(maj, min) 0
  19 #endif
  20
  21 #define QEMU_NORETURN __attribute__ ((__noreturn__))
  22
  23 #if QEMU_GNUC_PREREQ(3, 4)
  24 #define QEMU_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
  25 #else
  26 #define QEMU_WARN_UNUSED_RESULT
  27 #endif
  28
  29 #if QEMU_GNUC_PREREQ(4, 0)
  30 #define QEMU_SENTINEL __attribute__((sentinel))
  31 #else
  32 #define QEMU_SENTINEL
  33 #endif
  34
  35 #if QEMU_GNUC_PREREQ(4, 3)
  36 #define QEMU_ARTIFICIAL __attribute__((always_inline, artificial))
  37 #else
  38 #define QEMU_ARTIFICIAL
  39 #endif
  40
  41 #if defined(_WIN32)
  42 # define QEMU_PACKED __attribute__((gcc_struct, packed))
  43 #else
  44 # define QEMU_PACKED __attribute__((packed))
  45 #endif
  46
  47 #define QEMU_ALIGNED(X) __attribute__((aligned(X)))
  48
  49 #ifndef glue
  50 #define xglue(x, y) x ## y
  51 #define glue(x, y) xglue(x, y)
  52 #define stringify(s)    tostring(s)
  53 #define tostring(s)     #s
  54 #endif
  55
  56 #ifndef likely
  57 #if __GNUC__ < 3
  58 #define __builtin_expect(x, n) (x)
  59 #endif
  60
  61 #define likely(x)   __builtin_expect(!!(x), 1)
  62 #define unlikely(x)   __builtin_expect(!!(x), 0)
  63 #endif
  64
  65 #ifndef container_of
  66 #define container_of(ptr, type, member) ({                      \
  67         const typeof(((type *) 0)->member) *__mptr = (ptr);     \
  68         (type *) ((char *) __mptr - offsetof(type, member));})
  69 #endif
  70
  71 /* Convert from a base type to a parent type, with compile time checking.  */
  72 #ifdef __GNUC__
  73 #define DO_UPCAST(type, field, dev) ( __extension__ ( { \
  74     char __attribute__((unused)) offset_must_be_zero[ \
  75         -offsetof(type, field)]; \
  76     container_of(dev, type, field);}))
  77 #else
  78 #define DO_UPCAST(type, field, dev) container_of(dev, type, field)
  79 #endif
  80
  81 #define typeof_field(type, field) typeof(((type *)0)->field)
  82 #define type_check(t1,t2) ((t1*)0 - (t2*)0)
  83
  84 #define QEMU_BUILD_BUG_ON(x) \
  85     typedef char glue(qemu_build_bug_on__,__LINE__)[(x)?-1:1] __attribute__((unused));
  86
  87 #if defined __GNUC__
  88 # if !QEMU_GNUC_PREREQ(4, 4)
  89    /* gcc versions before 4.4.x don't support gnu_printf, so use printf. */
  90 #  define GCC_FMT_ATTR(n, m) __attribute__((format(printf, n, m)))
  91 # else
  92    /* Use gnu_printf when supported (qemu uses standard format strings). */
  93 #  define GCC_FMT_ATTR(n, m) __attribute__((format(gnu_printf, n, m)))
  94 #  if defined(_WIN32)
  95     /* Map __printf__ to __gnu_printf__ because we want standard format strings
  96      * even when MinGW or GLib include files use __printf__. */
  97 #   define __printf__ __gnu_printf__
  98 #  endif
  99 # endif
 100 #else
 101 #define GCC_FMT_ATTR(n, m)
 102 #endif
 103
 104 #endif /* COMPILER_H */