include/wrapper/compiler.h

   1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
   2  *
   3  * wrapper/compiler.h
   4  *
   5  * Copyright (C) 2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   6  */
   7
   8 #ifndef _LTTNG_WRAPPER_COMPILER_H
   9 #define _LTTNG_WRAPPER_COMPILER_H
  10
  11 #include <linux/compiler.h>
  12
  13 /*
  14  * Don't allow compiling with buggy compiler.
  15  */
  16
  17 #ifdef GCC_VERSION
  18
  19 /*
  20  * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58854
  21  */
  22 # ifdef __ARMEL__
  23 #  if GCC_VERSION >= 40800 && GCC_VERSION <= 40802
  24 #   error Your gcc version produces clobbered frame accesses
  25 #  endif
  26 # endif
  27 #endif
  28
  29 /*
  30  * READ/WRITE_ONCE were introduced in kernel 3.19 and ACCESS_ONCE
  31  * was removed in 4.15. Prefer READ/WRITE but fallback to ACCESS
  32  * when they are not available.
  33  */
  34 #ifndef READ_ONCE
  35 # define READ_ONCE(x)           ACCESS_ONCE(x)
  36 #endif
  37
  38 #ifndef WRITE_ONCE
  39 # define WRITE_ONCE(x, val)     ({ ACCESS_ONCE(x) = val; })
  40 #endif
  41
  42 #define __LTTNG_COMPOUND_LITERAL(type, ...)     (type[]) { __VA_ARGS__ }
  43
  44 #endif /* _LTTNG_WRAPPER_COMPILER_H */