Changes for the 5.9 release (the cctools-384 release):
- Removed the semicolon after the closing curly brace in the trailing endif
__cplusplus wrapper in <mach-o/dyld.h>. Radar bug #2748160.
Changes for the 5.9 release (the cctools-381 release):
- Added the LC_REQ_DYLD constant to <mach-o/loader.h> as a bit in the load
command that must be understood by the dynamic linker for the image to
execute properly.
Changes for the 5.9 release (the cctools-378 release):
- Added the extern "C" stuff in #if __cplusplus wrappers for <mach-o/dyld.h> .
Radar bug #2728016.
Changes for the 5.9 release (the cctools-370 release):
- Added the MH_NOMULTIDEFS flag to <mach-o/loader.h> .
- Added the hints_cmd and output_hints fields to the object structure in
<stuff/breakout.h> .
Changes for the 5.9 release (the cctools-369 release):
- Picked up the changes to <mach-o/arch.h> so that it has the extern "C" stuff
in #if __cplusplus wrappers.
- Added kld_load_from_memory & kld_load_basefile_from_memory for the dynamic
build variant of libkld. These APIs will be used by the Kernel's dynamic
OSObject patch code. This change is in <mach-o/kld.h> .
Changes for the 5.9 release (the cctools-367 release):
- Added swap_sub_library_command to <mach-o/swap.c>. Added
swap_sub_library_command() to <stuff/bytesex.h> . Added the LC_SUB_LIBRARY
load command and the sub_library_command struct to <mach-o/loader.h> .
Radar bug #2697458.
- Added swap_twolevel_hint(), swap_twolevel_hints_command() and the missing
swap_routines_command() to <mach-o/swap.c>. Added
swap_twolevel_hints_command() and swap_twolevel_hint() to <stuff/bytesex.h> .
Added the LC_TWOLEVEL_HINTS load command and the twolevel_hint struct to
<mach-o/loader.h> . Radar bug #2558069.
Changes for the 5.9 release (the cctools-365 release):
- Added NSAddImage(), NSLookupSymbolInImage() and NSIsSymbolNameDefinedInImage()
and their options to <mach-o/dyld.h>. Also NSOtherErrorInvalidArgs in the
NSOtherErrorNumbers enum in <mach-o/dyld.h> was added. Radar bug #2689833.
Changes for the 5.9 release (the cctools-360 release):
- Added the sections field to stuff/breakout.h for support of NO_TOC section
attribute. See notes in libstuff about writeout().
- Added the header file <mach-o/redo_prebinding.h> for the redo_prebinding(3)
API. Radar bug #2604014.
- Changed guess_short_name() to be __private_extern__ in
<stuff/guess_short_name.h> .
Changes for the 5.9 release (the cctools-359 release):
- Changed the comments about SELF_LIBRARY_ORDINAL in <mach-o/nlist.h> to
correctly reflect its usage.
- Removed the comment /* not yet implemented */ before
NSDestroyObjectFileImage() in <mach-o/dyld.h> as this was fixed as part of
Radar bug #2500014.
Changes for the 5.8 release (the cctools-357 release):
- Added CPU_SUBTYPE_POWERPC_7450 to <mach/machine.h> Radar bug #2599869.
Changes for the 5.8 release (the cctools-354 release):
- Fixed a type in <mach-o/loader.h> in describing MH_PRELOAD. Radar bug
#2571359.
Changes for the 5.8 release (the cctools-353 release):
- Moved the header files to /usr/include and /usr/local/include when RC_OS is
macos and RC_RELEASE is not Beaker, Bunsen, Gonzo or Kodiak. Radar bug
#2569880.
Changes for the 5.8 release (the cctools-350 release):
- Added the prototypes for NSIsSymbolNameDefinedWithHint(),
NSLookupAndBindSymbolWithHint() and _dyld_lookup_and_bind_with_hint() to
<mach-o/dyld.h>. Radar bug #2567184.
Changes for the 5.8 release (the cctools-349 release):
- Added the file <mach-o/dyld_gdb.h>. Radar bug #2559324.
Changes for the 5.8 release (the cctools-347 release):
- Added _dyld_register_func_for_remove_image() to <mach-o/dyld.h>.
- Added NSAddLibraryWithSearching() to <mach-o/dyld.h>. Radar bug #2535633.
Changes for the 5.8 release (the cctools-343 release):
- Changed REFERENCED_DYNAMICALLY back to 0x0010 as it was inadverntly changed
to 0x0080 which breaks strip(1) and binary compatiblity.
Changes for the 5.8 release (the cctools-342 release):
- Added the sub_client_command load command to <mach-o/loader.h> and swap
routine to <mach-o/swap.h>. Radar bug 2533649.
- Added MH_TWOLEVEL and MH_FORCE_FLAT to <mach-o/loader.h> for two-level name
space support. Radar bug #2534043.
- Added comments and macros to <mach-o/nlist.h> for two-level name space
support. Radar bug #2534043.
Changes for the 5.8 release (the cctools-341 release):
- Added the sub_umbrella_command load command to <mach-o/loader.h>. Radar bug
#2530028.
- Added the header file <mach-o/kld.h> and changed the Makefile to install it.
- Changed <mach-o/sarld.h> so that sa_rld_output_addr and sa_rld_output_size
are private_externs and noted in the comment they are not part of the extenal
API. Radar bug #2523649.
Changes for the 5.7 release (the cctools-336 release):
- Added the section attribute S_ATTR_NO_TOC section contains coalesced symbols
that are not to be in a ranlib table of contents. Radar bug #2494286.
Changes for the 5.7 release (the cctools-334 release):
- Changed guess_short_name()'s has_suffix argument to return_suffix to a pointer
to the suffix so checksyms could check for "_debug".
- Added NSOtherErrorLazyInit to the NSOtherErrorNumbers enum typedef for the
few errors that can happen setting up the exception handler for lazy inits.
Radar bug #2490396.
- Added MH_LAZY_INIT to <mach-o/loader.h> for "Lazy initialization of specified
libraries in a prebound launch". Radar bug #2490396.
Changes for the 5.7 release (the cctools-332 release):
- Changed the following routines to take a disablewarnings flag which was added
to seg_addr_table(1): get_symfile_for_dylib() and get_dstfile_for_dylib() in
the header file "stuff/dylib_roots.h" and dstLocForDylib(),
get_dstfile_for_dylib() and LocForDylib() in the header file "stuff/SymLoc.h"
(Radar bug #2482327).
Changes for the 5.7 release (the cctools-329 release):
- Change the parameters to the unimplemented NSReplaceModule() api to change
the last two parameters to just one parameter named options to match what
is done in NSLinkModule() and NSUnLinkModule(). Radar bug #2469558.
- Changed the fields names iinit and ninit in struct dylib_module in
<mach-o/loader.h> to iinit_iterm and ninit_nterm reflect that they now contain
the indexes and counts into the init and term sections. Radar bug #2469527.
- Added the prototype for the new function _dyld_debug_task_from_core() to
<mach-o/dyld_debug.h>. Radar bug #2155790.
- Added the prototype for the new function NSCreateCoreFileImageFromFile()
to <mach-o/dyld.h>. Also added a new enum for other link edit errors and made
some other minor changes. Radar bug #2155790.
Changes for the 5.7 release (the cctools-327 release):
- Left where the headers get installed in the System Framework. So they will
continue to be installed in /System/Library/Frameworks/System.framework/...
And maybe sometime post-DP4 they will be in
/MacOSX/System/Frameworks/System.framework/...
Changes for the 5.6 release (the cctools-323 release):
- Changed back where the headers get installed in the System Framework
back to /System/Library/Frameworks/System.framework/... from
/MacOSX/System/Frameworks/System.framework/.... for the Space release. This
won't change till post-DP4.
Changes for the 5.6 release (the cctools-320 release):
- Changed the Makefile to install "stuff/bool.h" into the local include mach-o
directory as an egregious hack for sampler. See the dyld notes.
(Radar bug #2376135).
- Added the new LC_SUB_FRAMEWORK load command to support "Guarding against
direct linking of non-umbrella frameworks". Various public and private
header files were updated to supply this support, <mach-o/loader.h>,
<mach-o/swap.h> (also the missing prototypes for other functions were added),
"stuff/bytesex.h", "stuff/seg_addr_table.h" (the routine guess_short_name()
was broken out and the new header "guess_short_name.h" was added).
Radar bug #2443212.
Changes for the 5.5 release (the cctools-314 release):
- Added the definition of the struct dyld_debug_error_data and
the API _dyld_debug_set_error_func() to register a function to be called
when one of the dyld debug API's fails to <mach-o/dyld_debug.h> Radar bug
#2421770.
- Added DYLD_IMAGE_REMOVED to the dyld_event_type enum for removal of plugins
in <mach-o/dyld_debug.h> Radar bug #2421760.
Changes for the 5.5 release (the cctools-308 release):
- Added the following code to dyld.h:
#ifndef __cplusplus
#define DYLD_BOOL bool
#endif
and changed all occurences of "bool" to "DYLD_BOOL". Radar bug #2412898.
Changes for the 5.5 release (the cctools-307 release):
- Added N_BINCL, N_EINCL and N_EXCL to mach-o/stabs.h for begin/end/exclude
include files. Radar bug #2410704.
- Added N_BNSYM and N_ENSYM to mach-o/stabs.h for begin/end section symbols
for used with coalesced symbols. Radar bug #2411273.
- Added CPU_SUBTYPE_POWERPC_7400 to cctools copy of mach/machine.h. The
Beaker2O6 has this as CPU_SUBTYPE_POWERPC_Max (both have the value 10).
Radar bug #2397523.
Changes for the 5.4 release (the cctools-300 release):
- Changed the Makefile so headers are not in installed for make install for
RC_OS=macos. Radar Bug #2370826.
- Added the new load command LC_ROUTINES for library initialization routines.
- Added the new section type S_COALESCED for coalesced symbols.
Changes for the 5.3 release (the cctools-286 release):
- Added the new section type S_MOD_TERM_FUNC_POINTERS for termination function
pointers.
Changes for the 5.3 release (the cctools-285 release):
- Changed the #ifdef NeXT in <gnu/exec.h> to #ifdef NeXT_MOD and to define
NeXT_MOD if not defined.
- Updated again mach/ppc/thread_status.h to the Beaker1E1 MacOS X version.
Also changed the macros
MACHINE_THREAD_STATE
MACHINE_THREAD_STATE_COUNT
THREAD_MACHINE_STATE_MAX
to:
PPC_MACHINE_THREAD_STATE
PPC_MACHINE_THREAD_STATE_COUNT
PPC_THREAD_MACHINE_STATE_MAX
So that mach/{ppc,i386,etc}/thread_status.h can all be included in the same
file without warnings about redefined macros.
- Changed #import <sys/types.h> in ranlib.h to #include <sys/types.h>
Radar Bug #2303937.
Changes for the MacOS X bring up (the cctools-282 release):
- Added the file stuff/openstep_mach.h which has defines to allow cctools
to be built on openstep now that the code has been changed to use Mach 3.0
names.
- Changed the Makefile to allow for RC_OS=macos for MacOS X builds.
- Chanded standalone/libsa.h to used mach_port_t for port_t, vm_task_t and
host_t.
- Changed all the port_t and task_t to mach_port_t in mach-o/dyld_debug.h .
Also added a hack to typedef msg_header_t and msg_type_t to int for bring up.
- Changed vm_task_t to mach_port_t in vm_flush_cache.c to build for MacOS X.
- Updated mach/ppc/thread_status.h to the MacOS X version. The files in the
architecture/ppc are no longer needed and the Makefile was changed.
- Copied in mach/i386/thread_status.h from Rhapsody Atlas1G1 for porting to
MacOS X since this header file is not yet part of the header set.
Changes for the 5.2 release (the cctools-278 release):
- Changed where <mach-o/rld.h> gets installed. It is now a private header as
it uses <streams/streams.h> which is a private header.
- Chanded <mach-o/dyld.h> to not include <streams/streams.h>
Changes for the 5.2 release (the cctools-274 release):
- Removed the i586SX cpusubtype and added the new intel x86 subtypes and macros
for families and models. Radar bug #2231830.
Changes for the 5.2 release (the cctools-267 release):
- Added <mach-o/getsect.h>. Radar bug #2227839.
- Added:
#if defined(__MWERKS__) && !defined(__private_extern__)
#define __private_extern__ __declspec(private_extern)
#endif
to many headers to allow compiling with MetroWerks compiler. Radar bug
#2227678.
- Changed architecture/m88k/fp_regs.h line:
#ifdef __GNUC__
unsigned x[4] __attribute__(( aligned(16) ));
#else
unsigned x[4];
#endif
to deal with MetroWerks compiler. Radar bug #2227678.
- Removed the #ifded 0 around swap_dysymtab_command() in <mach-o/swap.h>.
Radar bug #2227474.
Changes for the 5.1 release (the cctools-260 release):
- Added -c to all the install commands in the Makefile.
Changes for the 5.1 release (the cctools-253 release):
- Changed where the headers get installed to match the new directory layout for
Preimer.
Changes for the 5.1 release (the cctools-248 release):
- Changed over to base gmon.h on the 4.4bsd file. For Rhapsody this file is
installed by another project. There is a local copy if the file <sys/gmon.h>
here until the modified file makes it into the release. The 4.2
<mach-o/gmon.h> file is no longer installed for RC_OS teflon.
Changes for the 5.1 release (the cctools-247 release):
- Added MKDIRS if code to the Makefile to build native on Rhapsody.
- Changed the Makefile to use gnutar instead of tar because it works on Rhapsody
where tar does not.
- Moved m68k and sparc mach-o headers to local headers for install.
- Removed the comment allowing the moduleName parameter of NSLinkModule() in
dyld.h to be NULL (Radar 1670835).
Changes for the 5.0 release (the cctools-240 release):
- Changed it so gnu/a.out.h and gnu/exec.h are not installed with installGNUsrc
and installMWsrc because they are encumbered.
Changes for the 5.0 release (the cctools-235 release):
- Added PPC_RELOC_JBSR to ppc/reloc.h .
- Picked up the comments from the OpenBSD headers and replaced the comments in
nlist.h, reloc.h, gmon.h and stab.h.
Changes for the 5.0 release (the cctools-234 release):
- Ifdef'ed the inline functions using asm()'s in architecture because of the
Teflon use of -fkeep-inlines causing things not to compile.
Changes for the 5.0 release (the cctools-224 release):
- Added mach-o/ranlib.h from bsd/ranlib.h changing off_t to unsigned long.
This was needed for Teflon as off_t is a long long (64 bits).
- Added a mach-o/sparc/swap.h, mach-o/ppc/swap.h, mach-o/i860/swap.h and a
mach-o/m88k/swap.h .
- Picked up the PowerPC subtypes from unix-42/mach/machine.h .
- Changed the Makefile to install mach-o/ppc/reloc.h in NextDeveloper/Headers.
Changes for the 5.0 release (the cctools-221 release):
- Picked up correct Rhapsody mach/ppc/thread_status.h and updated
stuff/bytesex.h.
Changes for the 4.0 release (the cctools-133 release):
- Picked up sparc changes to architecture/sparc/reg.h.
- Picked up sparc changes to mach/sparc/thread_status.h.
- Picked up sparc changes to stuff/bytesex.h for prototype of
swap_sparc_thread_state_fpu().
- Picked up sparc changes to mach-o/sparc/reloc.h.
Changes for the 4.0 release (the cctools-132 release):
- Removed the 2.0 compatiblity header files.
- Picked up the files mach/sparc/thread_status.h and architecture/sparc/reg.h
Changes for the 3.3 release (the cctools-125 release):
- Picked up installing 2.0Compatiblity/sys/loader.h
- Added installing nlist.h stab.h loader.h fat.h (bug #31334).
Changes for the 3.3 release (the cctools-120 release):
- Added the file <mach-o/dyld.h>
Changes for the 3.3 release (the cctools-119 release):
- Picked up the first changes for sparc (sparc/reloc.h) the work is not
complete.
Changes for the 3.3 release (the cctools-104 release):
- Changed the name of the first parameter of swap_ident_command() from id to
id_cmd (in bytesex.h). The compiler is treating this as a reserved word.
Changes for the 3.3 release (the cctools-102 release):
- Integrated in the hppa support.
different include/Makefile (integrated for cctools-102)
Using cctoolshppa-37. mach-o/hppa/reloc.h is new.
different include/gnu/a.out.h (integrated for cctools-102)
Using cctoolshppa-37. Added:
#ifdef HPPA
#include "mach-o/hppa/reloc.h"
#endif
different include/mach/machine.h (integrated for cctools-102)
Using cctoolshppa-37. New constants for hppa and badly integrated the
existing contants:
#define CPU_TYPE_ANY ((cpu_type_t) -1)
#define CPU_SUBTYPE_MULTIPLE ((cpu_subtype_t) -1)
#define CPU_SUBTYPE_LITTLE_ENDIAN ((cpu_subtype_t) 0)
#define CPU_SUBTYPE_BIG_ENDIAN ((cpu_subtype_t) 1)
which were scattered though out the file and moved from their comment.
Email sent to Josh on this one (who forwarded it to Mac).
different include/stuff/bytesex.h (integrated for cctools-102)
Using cctoolshppa-37. New routines for swaping hppa's threads.
Only in cctoolshppa-37/include/mach: hppa (integrated for cctools-102)
Pick up include/mach/hppa/thread_status.h from cctoolshppa-37.
Only in cctoolshppa-37/include/mach-o: hppa (integrated for cctools-102)
Pick up include/mach-o/hppa/reloc.h from cctoolshppa-37. But has
HPPA_RELOC_NORELOC which is used in hppa.c. HPPA_RELOC_NORELOC pulled
from reloc.h and NO_RELOC defined as 0x10 (out side the range of r_type:4)
in hppa.h and NO_RELOC used in hppa.c.
Changes for the 3.1 release (the cctools-22 release):
- Added to mach/machine.h the following cpp macros (bug #32553):
#define CPU_TYPE_ANY ((cpu_type_t) -1)
#define CPU_SUBTYPE_LITTLE_ENDIAN ((cpu_subtype_t) 0)
#define CPU_SUBTYPE_BIG_ENDIAN ((cpu_subtype_t) 1)
Changes for the 3.1 release (the cctools-15 release):
- Picked up the proper mach/m98k/thread_status.h and the six included files
to make it compile.
Changes for the 3.1 release (the cctools-13 release):
- Added the m98k (PowerPC) architecture. This includes a kludged
mach/m98k/thread_status.h with only an entry point.
Changes for the 3.1 release (the cctools-6 release):
- Changed mach/i386/thread_status.h so the m68k compiler will compile this the
same as the i386 compiler. The change was to change the "unsigned int :0" to
"unsigned short pad_??".
Changes for the 3.1 release (the cctools-5 release):
- Picked up the lono teams cctools-4_2 mach/i386/thread_status.h as well as
machdep/i386/frame.h machdep/i386/fpregs.h machdep/i386/sel.h .
- Changed "struct i386_thread_state *cpu," to "i386_thread_state_t *cpu,"
in bytesex.h for the lono team.
Changes for the 3.1 release (the cctools-4 release):
- Moved the ix86 directory to i386.
Changes for the 3.0 release (the -56 compiler release):
- Fixed some typos in mach-o/reloc.h in the __LITTLE_ENDIAN__ code (bug #19639).
Changes for the 3.0 release (the -53 compiler release):
- Removed the local copy of mach/m88k/thread_status.h .
Changes for the 3.0 release (the -47 compiler release):
- Split of the reloc.h header file:
part of mach-o/reloc.h -> mach-o/m88k/reloc.h
part of mach-o/reloc.h -> mach-o/i860/reloc.h
- Switch over to the newer header file organization.
m88k/mach/thread_status.h -> mach/m88k/thread_status.h
ix86/mach/thread_status.h -> mach/ix86/thread_status.h
i860/mach/thread_status.h -> mach/i860/thread_status.h
m88k/disasm.h -> mach-o/m88k/disasm.h
m88k/parseinst.h -> mach-o/m88k/parseinst.h
Changes for the 3.0 release (the -44 compiler release):
- Switch over to the new header file organization.
Changes for the 3.0 release (the -36 compiler release):
- Added the 88k disassembler header file but these are not installed.
Changes for the 3.0 release (the -34 compiler release):
- Added installsrc, installIBMsrc and installGNUsrc targets to the Makefile.
Changes for the 3.0 release (the -33 compiler release):
- sys/machine.h: (this is owned by the OS group and will be given back to them)
* 16-Oct-90 Compiler group (comp) at NeXT.
* Replaced the 88k cpu_subtype CPU_SUBTYPE_MMAX_JPC with
* CPU_SUBTYPE_MC88100 and CPU_SUBTYPE_MC88110 to match 68k types.
/*
* MC88000 subtypes
*/
#define CPU_SUBTYPE_MC88100 ((cpu_subtype_t) 1)
#define CPU_SUBTYPE_MC88110 ((cpu_subtype_t) 2)
The I860 CPU type in the NDTools 7 conflicts with the CPU_TYPE_I386 which is
also 7. In talking with Mike Paquette (10/16/90) he said it is ok to change
CPU_TYPE_I860 to whatever and he will recompile NextDimention.
The three I860 additions were as follows:
* 16-Aug-89 Mike Paquette (mpaque) at NeXT
* Added I860 CPU type and subtypes for big or little-endian data
* implementation.
#define CPU_TYPE_I860 ((cpu_type_t) 7) <<<will be 14>>>
/*
* I860 subtypes
*/
#define CPU_SUBTYPE_LITTLE_ENDIAN ((cpu_subtype_t) 0)
#define CPU_SUBTYPE_BIG_ENDIAN ((cpu_subtype_t) 1)
- machine/thread_status.h: where "machine" is a symbolic link to "next"
(this is owned by the OS group and will be given back to them)
In talking to Mike DeMoney on (10/16/90) he came up with the following
structure to handle the multiple machines specific files. These would
be the directories in /usr/include (or in the kernel's header file area):
next68k/ was just next/
next88k/
next860/
A symbolic link from "next to "next" will be added for compatiblity and
the symbolic "machine" will point to the directory the kernel is configured
for.
- next860/thread_status.h:
This is to be owned by someone like Mike Paquette. It is the file that
discrbes JUST the i860 thread state.
- next88k/thread_status.h:
This is to be owned by the OS group. The compiler group made a first
cut at it.
Changes for the Warp ?? release (the -25 compiler release):
- Added the scattered_relocation_info struct to reloc.h
Changes for the Warp ?? release (the -24 compiler release):
- Added #import <sys/loader.h> to ldsyms.h (bug 6031).
- Added rld.h to be installed in /usr/include.
Changes for the 2.0 impulse X.X release (the -19 compiler release):
- Updated ldsyms.h to match the new link editor. Basicly removing lots of old
stuff.
- Added one missing ';' in symseg.h to get rid of a warning.
- Removed the temporay copies of <ranlib.h> and <sys/loader.h> now that the
Impulse 0.02 release has the right versions.
- Added temporary copies of <nlist.h> and <sys/machine.h> until the next libc
and mk projects get released and the correct versions are in /usr/include.
Changes for the 0.93 release (the -12 compiler release):
- No longer install symseg.h
- Now own sys/exec.h as a part of a.out.h
Changes for the 0.82 release (the -8 compiler release):
- Changed the Makefile to install in /usr/include
Changes for the 0.82 release (the -7 compiler release):
- Added header_addr to fvmlib load and id commands.
- Added the SEG_PAGEZERO segment name to sys/loader.h for the segment created
to protect page zero for NULL pointers.
Changes for the 0.81 release (the -6 compiler release):
- The following files to reflect what is contained in a true mach-O object
file (relocatables and other formats):
nlist.h
reloc.h (new)
symseg.h
stab.h
These along with <sys/loader.h> are now the offical files that mach-O object
tools should reference. The file <a.out.h> has been updated with the same
changes but will go away in the 1.0 release or renamed to <a.out.h.old>.
The logical changes are as follows:
To the nlist structure (also see comments in <nlist.h> and <stab.h>):
The modifications from the original format were changing n_other (an unused
field) to n_sect and the addition of the N_SECT type. All mach-O symbols
defined a section (for example what use to be N_TEXT, N_DATA and N_BSS) now
have the type N_SECT.
If the type is N_SECT then the n_sect field contains an ordinal of the
section the symbol is defined in. The sections are numbered from 1 and
refer to sections in order they appear in the load commands for the file
they are in. This means the same ordinal may very well refer to different
sections in different files.
The n_value field for all symbol table entries (including N_STAB's) gets
updated by the link editor based on the value of it's n_sect field and where
the section n_sect references gets relocated. If the value of the n_sect
field is NO_SECT then it's n_value field is not changed by the link editor.
The comments in <stab.h> have been updated to reflect this.
Common symbols are represented by undefined (N_UNDF) external (N_EXT) types
who's values (n_value) are non-zero. In which case the value of the n_value
field is the size (in bytes) of the common symbol.
Absolute, undefined and common symbols are NOT in any section and thus their
n_sect field must be NO_SECT to indicate this and avoid having their n_value
field changed.
To the relocation_info structure (see the comments in <reloc.h>):
The modifications from the original format were changing the value
of the r_symbolnum field for "local" (r_extern == 0) relocation entries.
In 4.3bsd a.out objects if r_extern is zero then r_symbolnum is an ordinal
for the segment the symbol being relocated is in. These ordinals are the
symbol types N_TEXT, N_DATA, N_BSS or N_ABS. In mach-O object files these
ordinals refer to the sections in the object file they are in. The first
section has the ordinal 1, the second 2, and so on. This means that the
same ordinal in two different object files could refer to two different
sections. And further could have still different ordinals when combined
by the link-editor. The value R_ABS is used for relocation entries for
absolute symbols which need no further relocation.
To the symseg structures (see the comments in <symseg.h>):
To handle an arbitrary number of segments and sections the symbol_root,
the indirect_root and the shlib_root have new structures in a mach-O
object file. The change to these structures was to replace the fields
relating to where a segment was loaded with a load map.
The load map describes where the parts the relocatable object have been
loaded in the executable. The enitre address space of the relocatable
is to be covered by all the map entries. There may be multiple map entries
for a single section or one map entry for multiple sections. This allows
the link editor to scatter load a section based on information that improves
performance by increasing the locality of reference.
- The N_INDR symbol type was added for indirect symbols (to support building
the ANSI C library).
If the type is N_INDR then the symbol is defined to be the same as another
symbol. In this case the n_value field is an index into the string table
of the other symbol's name. When the other symbol is defined then they both
take on the defined type and value.
- Changed the loader defined symbol names _etext, _edata, and _end to __etext,
__edata, __end so not to pollute the name space of ANSI C programs. There
are now macros for these symbols. The ANSI C library will have objects with
indirect symbols so that old names will still work if the program is linked
with the ANSI C library.