gcc/gthr-lynx.h

   1 /* Threads compatibility routines for libgcc2 and libobjc for
   2    LynxOS.  */
   3 /* Compile this one with gcc.  */
   4 /* Copyright (C) 2004 Free Software Foundation, Inc.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 2, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING.  If not, write to the Free
  20 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  21 02110-1301, USA.  */
  22
  23 /* As a special exception, if you link this library with other files,
  24    some of which are compiled with GCC, to produce an executable,
  25    this library does not by itself cause the resulting executable
  26    to be covered by the GNU General Public License.
  27    This exception does not however invalidate any other reasons why
  28    the executable file might be covered by the GNU General Public License.  */
  29
  30 #ifndef GCC_GTHR_LYNX_H
  31 #define GCC_GTHR_LYNX_H
  32
  33 #ifdef _MULTITHREADED
  34
  35 /* Using the macro version of pthread_setspecific leads to a
  36    compilation error.  Instead we have two choices either kill all
  37    macros in pthread.h with defining _POSIX_THREADS_CALLS or undefine
  38    individual macros where we should fall back on the function
  39    implementation.  We choose the second approach.  */
  40
  41 #include <pthread.h>
  42 #undef pthread_setspecific
  43
  44 /* When using static libc on LynxOS, we cannot define pthread_create
  45    weak.  If the multi-threaded application includes iostream.h,
  46    gthr-posix.h is included and pthread_create will be defined weak.
  47    If pthead_create is weak its defining module in libc is not
  48    necessarily included in the link and the symbol is resolved to zero.
  49    Therefore the first call to it will crash.
  50
  51    Since -mthreads is a multilib switch on LynxOS we know that at this
  52    point we are compiling for multi-threaded.  Omitting the weak
  53    definitions at this point should have no effect.  */
  54
  55 #undef  GTHREAD_USE_WEAK
  56 #define GTHREAD_USE_WEAK 0
  57
  58 #include "gthr-posix.h"
  59
  60 #else
  61 #include "gthr-single.h"
  62 #endif
  63
  64 #endif /* GCC_GTHR_LYNX_H */