gcconfig.h

gcc的组建

# ifdef VAX
#   define MACH_TYPE "VAX"
#   define ALIGNMENT 4	/* Pointers are longword aligned by 4.2 C compiler */
    extern char etext[];
#   define DATASTART ((ptr_t)(etext))
#   ifdef BSD
#	define OS_TYPE "BSD"
#	define HEURISTIC1
			/* HEURISTIC2 may be OK, but it's hard to test. */
#   endif
#   ifdef ULTRIX
#	define OS_TYPE "ULTRIX"
#	define STACKBOTTOM ((ptr_t) 0x7fffc800)
#   endif
# endif

# ifdef RT
#   define MACH_TYPE "RT"
#   define ALIGNMENT 4
#   define DATASTART ((ptr_t) 0x10000000)
#   define STACKBOTTOM ((ptr_t) 0x1fffd800)
# endif

# ifdef SPARC
#   define MACH_TYPE "SPARC"
#   if defined(__arch64__) || defined(__sparcv9)
#     define ALIGNMENT 8
#     define CPP_WORDSZ 64
#     define ELF_CLASS ELFCLASS64
#   else
#     define ALIGNMENT 4	/* Required by hardware	*/
#     define CPP_WORDSZ 32
#   endif
#   define ALIGN_DOUBLE
#   ifdef SUNOS5
#	define OS_TYPE "SUNOS5"
	extern int _etext[];
	extern int _end[];
	extern ptr_t GC_SysVGetDataStart();
#       define DATASTART GC_SysVGetDataStart(0x10000, _etext)
#	define DATAEND (_end)
#	if !defined(USE_MMAP) && defined(REDIRECT_MALLOC)
#	    define USE_MMAP
	    /* Otherwise we now use calloc.  Mmap may result in the	*/
	    /* heap interleaved with thread stacks, which can result in	*/
	    /* excessive blacklisting.  Sbrk is unusable since it	*/
	    /* doesn't interact correctly with the system malloc.	*/
#	endif
#       ifdef USE_MMAP
#         define HEAP_START (ptr_t)0x40000000
#       else
#	  define HEAP_START DATAEND
#       endif
#	define PROC_VDB
/*	HEURISTIC1 reportedly no longer works under 2.7.  		*/
/*  	HEURISTIC2 probably works, but this appears to be preferable.	*/
/*	Apparently USRSTACK is defined to be USERLIMIT, but in some	*/
/* 	installations that's undefined.  We work around this with a	*/
/*	gross hack:							*/
#       include <sys/vmparam.h>
#	ifdef USERLIMIT
	  /* This should work everywhere, but doesn't.	*/
#	  define STACKBOTTOM USRSTACK
#       else
#	  define HEURISTIC2
#       endif
#	include <unistd.h>
#       define GETPAGESIZE()  sysconf(_SC_PAGESIZE)
		/* getpagesize() appeared to be missing from at least one */
		/* Solaris 5.4 installation.  Weird.			  */
#	define DYNAMIC_LOADING
#   endif
#   ifdef SUNOS4
#	define OS_TYPE "SUNOS4"
	/* [If you have a weak stomach, don't read this.]		*/
	/* We would like to use:					*/
/* #       define DATASTART ((ptr_t)((((word) (etext)) + 0x1fff) & ~0x1fff)) */
	/* This fails occasionally, due to an ancient, but very 	*/
	/* persistent ld bug.  etext is set 32 bytes too high.		*/
	/* We instead read the text segment size from the a.out		*/
	/* header, which happens to be mapped into our address space	*/
	/* at the start of the text segment.  The detective work here	*/
	/* was done by Robert Ehrlich, Manuel Serrano, and Bernard	*/
	/* Serpette of INRIA.						*/
	/* This assumes ZMAGIC, i.e. demand-loadable executables.	*/
#	define TEXTSTART 0x2000
#       define DATASTART ((ptr_t)(*(int *)(TEXTSTART+0x4)+TEXTSTART))
#	define MPROTECT_VDB
#	define HEURISTIC1
# 	define DYNAMIC_LOADING
#   endif
#   ifdef DRSNX
#	define OS_TYPE "DRSNX"
	extern ptr_t GC_SysVGetDataStart();
	extern int etext[];
#       define DATASTART GC_SysVGetDataStart(0x10000, etext)
#	define MPROTECT_VDB
#       define STACKBOTTOM ((ptr_t) 0xdfff0000)
#	define DYNAMIC_LOADING
#   endif
#   ifdef LINUX
#     define OS_TYPE "LINUX"
#     ifdef __ELF__
#       define DYNAMIC_LOADING
#     else
          Linux Sparc/a.out not supported
#     endif
      extern int _end[];
      extern int _etext[];
#     define DATAEND (_end)
#     define SVR4
      extern ptr_t GC_SysVGetDataStart();
#     ifdef __arch64__
#	define DATASTART GC_SysVGetDataStart(0x100000, _etext)
#     else
#       define DATASTART GC_SysVGetDataStart(0x10000, _etext)
#     endif
#     define LINUX_STACKBOTTOM
#   endif
#   ifdef OPENBSD
#     define OS_TYPE "OPENBSD"
#     define STACKBOTTOM ((ptr_t) 0xf8000000)
      extern int etext[];
#     define DATASTART ((ptr_t)(etext))
#   endif
#   ifdef NETBSD
#     define OS_TYPE "NETBSD"
#     define HEURISTIC2
#     ifdef __ELF__
#	define DATASTART GC_data_start
#	define DYNAMIC_LOADING
#     else
	extern char etext[];
#	define DATASTART ((ptr_t)(etext))
#     endif
#   endif
# endif

# ifdef I386
#   define MACH_TYPE "I386"
#   if defined(__LP64__) || defined(_WIN64)
#     define CPP_WORDSZ 64
#     define ALIGNMENT 8
#   else
#     define CPP_WORDSZ 32
#     define ALIGNMENT 4
			/* Appears to hold for all "32 bit" compilers	*/
			/* except Borland.  The -a4 option fixes 	*/
			/* Borland.					*/
                        /* Ivan Demakov: For Watcom the option is -zp4. */
#   endif
#   ifndef SMALL_CONFIG
#     define ALIGN_DOUBLE /* Not strictly necessary, but may give speed   */
			  /* improvement on Pentiums.			  */
#   endif
#   ifdef HAVE_BUILTIN_UNWIND_INIT
#	define USE_GENERIC_PUSH_REGS
#   endif
#   ifdef SEQUENT
#	define OS_TYPE "SEQUENT"
	extern int etext[];
#       define DATASTART ((ptr_t)((((word) (etext)) + 0xfff) & ~0xfff))
#       define STACKBOTTOM ((ptr_t) 0x3ffff000) 
#   endif
#   ifdef BEOS
#     define OS_TYPE "BEOS"
#     include <OS.h>
#     define GETPAGESIZE() B_PAGE_SIZE
      extern int etext[];
#     define DATASTART ((ptr_t)((((word) (etext)) + 0xfff) & ~0xfff))
#   endif
#   ifdef SUNOS5
#	define OS_TYPE "SUNOS5"
        extern int _etext[], _end[];
  	extern ptr_t GC_SysVGetDataStart();
#       define DATASTART GC_SysVGetDataStart(0x1000, _etext)
#	define DATAEND (_end)
/*	# define STACKBOTTOM ((ptr_t)(_start)) worked through 2.7,  	*/
/*      but reportedly breaks under 2.8.  It appears that the stack	*/
/* 	base is a property of the executable, so this should not break	*/
/* 	old executables.						*/
/*  	HEURISTIC2 probably works, but this appears to be preferable.	*/
#       include <sys/vm.h>
#	define STACKBOTTOM USRSTACK
/* At least in Solaris 2.5, PROC_VDB gives wrong values for dirty bits. */
/* It appears to be fixed in 2.8 and 2.9.				*/
#	ifdef SOLARIS25_PROC_VDB_BUG_FIXED
#	  define PROC_VDB
#	endif
#	define DYNAMIC_LOADING
#	if !defined(USE_MMAP) && defined(REDIRECT_MALLOC)
#	    define USE_MMAP
	    /* Otherwise we now use calloc.  Mmap may result in the	*/
	    /* heap interleaved with thread stacks, which can result in	*/
	    /* excessive blacklisting.  Sbrk is unusable since it	*/
	    /* doesn't interact correctly with the system malloc.	*/
#	endif
#       ifdef USE_MMAP
#         define HEAP_START (ptr_t)0x40000000
#       else
#	  define HEAP_START DATAEND
#       endif
#   endif
#   ifdef SCO
#	define OS_TYPE "SCO"
	extern int etext[];
#   	define DATASTART ((ptr_t)((((word) (etext)) + 0x3fffff) \
				  & ~0x3fffff) \
				 +((word)etext & 0xfff))
#	define STACKBOTTOM ((ptr_t) 0x7ffffffc)
#   endif
#   ifdef SCO_ELF
#       define OS_TYPE "SCO_ELF"
        extern int etext[];
#       define DATASTART ((ptr_t)(etext))
#       define STACKBOTTOM ((ptr_t) 0x08048000)
#       define DYNAMIC_LOADING
#	define ELF_CLASS ELFCLASS32
#   endif
#   ifdef DGUX
#	define OS_TYPE "DGUX"
	extern int _etext, _end;
	extern ptr_t GC_SysVGetDataStart();
#	define DATASTART GC_SysVGetDataStart(0x1000, &_etext)
#	define DATAEND (&_end)
#	define STACK_GROWS_DOWN
#	define HEURISTIC2
#	include <unistd.h>
#	define GETPAGESIZE()  sysconf(_SC_PAGESIZE)
#	define DYNAMIC_LOADING
#	ifndef USE_MMAP
#	  define USE_MMAP
#	endif /* USE_MMAP */
#	define MAP_FAILED (void *) -1
#	ifdef USE_MMAP
#	  define HEAP_START (ptr_t)0x40000000
#	else /* USE_MMAP */
#	  define HEAP_START DATAEND
#	endif /* USE_MMAP */
#   endif /* DGUX */

#   ifdef LINUX
#	ifndef __GNUC__
	  /* The Intel compiler doesn't like inline assembly */
#	  define USE_GENERIC_PUSH_REGS
# 	endif
#	define OS_TYPE "LINUX"
#       define LINUX_STACKBOTTOM
#	if 0
#	  define HEURISTIC1
#         undef STACK_GRAN
#         define STACK_GRAN 0x10000000
	  /* STACKBOTTOM is usually 0xc0000000, but this changes with	*/
	  /* different kernel configurations.  In particular, systems	*/
	  /* with 2GB physical memory will usually move the user	*/
	  /* address space limit, and hence initial SP to 0x80000000.	*/
#       endif
#       if !defined(GC_LINUX_THREADS) || !defined(REDIRECT_MALLOC)
#	    define MPROTECT_VDB
#	else
	    /* We seem to get random errors in incremental mode,	*/
	    /* possibly because Linux threads is itself a malloc client */
	    /* and can't deal with the signals.				*/
#	endif
#	define HEAP_START (ptr_t)0x1000
		/* This encourages mmap to give us low addresses,	*/
		/* thus allowing the heap to grow to ~3GB		*/
#       ifdef __ELF__
#            define DYNAMIC_LOADING
#	     ifdef UNDEFINED	/* includes ro data */
	       extern int _etext[];
#              define DATASTART ((ptr_t)((((word) (_etext)) + 0xfff) & ~0xfff))
#	     endif
#	     include <features.h>
#	     if defined(__GLIBC__) && __GLIBC__ >= 2
#		 define SEARCH_FOR_DATA_START
#	     else
     	         extern char **__environ;
#                define DATASTART ((ptr_t)(&__environ))
			      /* hideous kludge: __environ is the first */
			      /* word in crt0.o, and delimits the start */
			      /* of the data segment, no matter which   */
			      /* ld options were passed through.        */
			      /* We could use _etext instead, but that  */
			      /* would include .rodata, which may       */
			      /* contain large read-only data tables    */
			      /* that we'd rather not scan.		*/
#	     endif
	     extern int _end[];
#	     define DATAEND (_end)
#	else
	     extern int etext[];
#            define DATASTART ((ptr_t)((((word) (etext)) + 0xfff) & ~0xfff))
#       endif
#	ifdef USE_I686_PREFETCH
	  /* FIXME: Thus should use __builtin_prefetch, but we'll leave that	*/
	  /* for the next rtelease.						*/
#	  define PREFETCH(x) \
	    __asm__ __volatile__ ("	prefetchnta	%0": : "m"(*(char *)(x)))
	    /* Empirically prefetcht0 is much more effective at reducing	*/
	    /* cache miss stalls for the targetted load instructions.  But it	*/
	    /* seems to interfere enough with other cache traffic that the net	*/
	    /* result is worse than prefetchnta.				*/
#         if 0 
	    /* Using prefetches for write seems to have a slight negative	*/
	    /* impact on performance, at least for a PIII/500.			*/
#	    define PREFETCH_FOR_WRITE(x) \
	      __asm__ __volatile__ ("	prefetcht0	%0": : "m"(*(char *)(x)))
#	  endif
#	endif
#	ifdef USE_3DNOW_PREFETCH
#	  define PREFETCH(x) \
	    __asm__ __volatile__ ("	prefetch	%0": : "m"(*(char *)(x)))
#	  define PREFETCH_FOR_WRITE(x) \
	    __asm__ __volatile__ ("	prefetchw	%0": : "m"(*(char *)(x)))
#	endif
#   endif
#   ifdef CYGWIN32
#       define OS_TYPE "CYGWIN32"
          extern int _data_start__[];
          extern int _data_end__[];
          extern int _bss_start__[];
          extern int _bss_end__[];
  	/* For binutils 2.9.1, we have			*/
  	/*	DATASTART   = _data_start__		*/
  	/*	DATAEND	    = _bss_end__		*/
  	/* whereas for some earlier versions it was	*/
  	/*	DATASTART   = _bss_start__		*/
  	/*	DATAEND	    = _data_end__		*/
  	/* To get it right for both, we take the	*/
  	/* minumum/maximum of the two.			*/
#     ifndef MAX
#   	define MAX(x,y) ((x) > (y) ? (x) : (y))
#     endif
#     ifndef MIN
#   	define MIN(x,y) ((x) < (y) ? (x) : (y))
#     endif
#       define DATASTART ((ptr_t) MIN(_data_start__, _bss_start__))
#       define DATAEND	 ((ptr_t) MAX(_data_end__, _bss_end__))
#	undef STACK_GRAN
#       define STACK_GRAN 0x10000
#       define HEURISTIC1
#   endif
#   ifdef OS2
#	define OS_TYPE "OS2"
 	    	/* STACKBOTTOM and DATASTART are handled specially in 	*/
		/* os_dep.c. OS2 actually has the right			*/
		/* system call!						*/
#	define DATAEND	/* not needed */
#	define USE_GENERIC_PUSH_REGS
#   endif
#   ifdef MSWIN32
#	define OS_TYPE "MSWIN32"
		/* STACKBOTTOM and DATASTART are handled specially in 	*/
		/* os_dep.c.						*/
#       ifndef __WATCOMC__
#	  define MPROTECT_VDB
#	endif
#       define DATAEND  /* not needed */
#   endif
#   ifdef MSWINCE
#	define OS_TYPE "MSWINCE"
#       define DATAEND  /* not needed */
#   endif
#   ifdef DJGPP
#       define OS_TYPE "DJGPP"
#       include "stubinfo.h"
        extern int etext[];
        extern int _stklen;
        extern int __djgpp_stack_limit;
#       define DATASTART ((ptr_t)((((word) (etext)) + 0x1ff) & ~0x1ff))
/* #       define STACKBOTTOM ((ptr_t)((word) _stubinfo + _stubinfo->size \
                                                     + _stklen)) */
#       define STACKBOTTOM ((ptr_t)((word) __djgpp_stack_limit + _stklen))
		/* This may not be right.  */
#   endif
#   ifdef OPENBSD
#	define OS_TYPE "OPENBSD"
#   endif
#   ifdef FREEBSD
#	define OS_TYPE "FREEBSD"
#	ifndef GC_FREEBSD_THREADS
#	    define MPROTECT_VDB
#	endif
#	define SIG_SUSPEND SIGUSR1
#	define SIG_THR_RESTART SIGUSR2
#	define FREEBSD_STACKBOTTOM
#	ifdef __ELF__
#	    define DYNAMIC_LOADING
#	endif
	extern char etext[];
	extern char * GC_FreeBSDGetDataStart();
#	define DATASTART GC_FreeBSDGetDataStart(0x1000, &etext)
#   endif
#   ifdef NETBSD
#	define OS_TYPE "NETBSD"
#	ifdef __ELF__
#	    define DYNAMIC_LOADING
#	endif
#   endif
#   ifdef THREE86BSD
#	define OS_TYPE "THREE86BSD"
#   endif
#   ifdef BSDI
#	define OS_TYPE "BSDI"
#   endif
#   if defined(OPENBSD) || defined(NETBSD) \
        || defined(THREE86BSD) || defined(BSDI)
#	define HEURISTIC2
	extern char etext[];
#	define DATASTART ((ptr_t)(etext))
#   endif
#   ifdef NEXT
#	define OS_TYPE "NEXT"
#	define DATASTART ((ptr_t) get_etext())
#	define STACKBOTTOM ((ptr_t)0xc0000000)
#	define DATAEND	/* not needed */
#   endif
#   ifdef DOS4GW