OSDev.org

*-*-rdos*)
  extra_parts="crtbegin.o crtend.o"
  ;;

...

i[34567]86-*-rdos*)
   tmake_file="$tmake_file i386/t-crtstuff t-crtstuff-pic t-libgcc-pic"
   ;;
x86_64-*-rdos*)
   tmake_file="$tmake_file i386/t-crtstuff t-crtstuff-pic t-libgcc-pic"
   ;;

/* RDOS uses .exe suffix */
#undef TARGET_EXECUTABLE_SUFFIX
#define TARGET_EXECUTABLE_SUFFIX ".exe"

#define TARGET_OS_CPP_BUILTINS()                \
  do                                                                    \
    {                                                                   \
        builtin_define ("__RDOS__");            \
        builtin_assert ("system=rdos");         \
    }                                                                   \
  while (0)

/* RDOS headers are C++-aware (and often use C++).  */
#define NO_IMPLICIT_EXTERN_C

#ifndef GCC_GTHR_RDOS_H
#define GCC_GTHR_RDOS_H

/* RDOS threads specific definitions.
   calls functions in rdos.s module  */

#define __GTHREADS 1

#ifdef __cplusplus
extern "C" {
#endif

extern int __rdos_thread_once_init (void);
extern int __rdos_thread_once (int handle, void (*func) (void));

extern int __rdos_thread_key_create (int handle, void (*dtor) (void *));
extern int __rdos_thread_key_delete (int handle);
extern void * __rdos_thread_getspecific (int handle);
extern int __rdos_thread_setspecific (int handle, const void *ptr);

extern int __rdos_thread_mutex_init (void);
extern int __rdos_thread_mutex_lock (int handle);
extern int __rdos_thread_mutex_trylock (int handle);
extern int __rdos_thread_mutex_unlock (int handle);

#define __gthread_key_t int
#define __gthread_once_t int
#define __gthread_mutex_t int
#define __gthread_recursive_mutex_t int

#define __GTHREAD_ONCE_INIT 0
#define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function
#define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_mutex_init_function

static inline int
__gthread_active_p (void)
{
  return 1;
}

static inline int
__gthread_once (__gthread_once_t *once, void (*func) (void))
{
  return __rdos_thread_once (*(int *)once, func);
}

static inline int
__gthread_key_create (__gthread_key_t *key, void (*dtor) (void *))
{
  return __rdos_thread_key_create (*(int *)key, dtor);
}

static inline int
__gthread_key_delete (__gthread_key_t key)
{
  return __rdos_thread_key_delete ((int)key);
}

static inline void *
__gthread_getspecific (__gthread_key_t key)
{
  return __rdos_thread_getspecific ((int)key);
}

static inline int
__gthread_setspecific (__gthread_key_t key, const void *ptr)
{
  return __rdos_thread_setspecific ((int)key, ptr);
}

static inline int
__gthread_mutex_lock (__gthread_mutex_t *mutex)
{
  return __rdos_thread_mutex_lock (*(int *)mutex);
}

static inline int
__gthread_mutex_trylock (__gthread_mutex_t *mutex)
{
  return __rdos_thread_mutex_trylock (*(int *)mutex);
}

static inline int
__gthread_mutex_unlock (__gthread_mutex_t *mutex)
{
  return __rdos_thread_mutex_unlock (*(int *)mutex);
}

static inline void
__gthread_mutex_init_function (__gthread_mutex_t *mutex)
{
  *mutex = __rdos_thread_mutex_init ();
}

static inline int
__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
{
  return __rdos_thread_mutex_lock (*(int *)mutex);
}

static inline int
__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
{
  return __rdos_thread_mutex_trylock (*(int *)mutex);
}

static inline int
__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
{
  return __rdos_thread_mutex_unlock (*(int *)mutex);
}

#ifdef __cplusplus
}
#endif

#endif /* ! GCC_GTHR_RDOS_H */

gcc -g -o test.exe file1.c file2.c
objcopy --only-keep-debug test.exe test.debug
strip -g test.exe
gdb test.exe
(gdb) sy test.debug

export TARGET=rdos
export PREFIX=/usr/local/rdos

mkdir build-binutils
cd build-binutils
../binutils-2.23.1/configure --target=$TARGET --prefix=$PREFIX --disable-nls
make all
make install

export PATH=$PATH:$PREFIX/bin
mkdir build-gcc-noheader
cd build-gcc-noheader
../gcc-4.8-20121202/configure --target=$TARGET --prefix=$PREFIX  --disable-nls --enable-languages=c,c++ --without-headers --disable-threads
make all-gcc
make install-gcc
make all-target-libgcc
make install-target-libgcc

mkdir build-newlib
cd build-newlib
../newlib-1.20.0/configure --target=$TARGET --prefix=$PREFIX --disable-nls
make all
make install

mkdir build-gcc
cd build-gcc
../gcc-4.8-20121202/configure --target=$TARGET --prefix=$PREFIX  --disable-nls --enable-languages=c,c++ --enable-threads
make all-gcc
make install-gcc
make all-target-libgcc
make install-target-libgcc