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2006-12-05 Eric Christopher <echristo@apple.com>
[pf3gnuchains/gcc-fork.git] / gcc / config / darwin.h
1 /* Target definitions for Darwin (Mac OS X) systems.
2    Copyright (C) 1989, 1990, 1991, 1992, 1993, 2000, 2001, 2002, 2003, 2004,
3    2005, 2006
4    Free Software Foundation, Inc.
5    Contributed by Apple Computer Inc.
6
7 This file is part of GCC.
8
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
12 any later version.
13
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING.  If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA.  */
23
24 #ifndef CONFIG_DARWIN_H
25 #define CONFIG_DARWIN_H
26
27 /* The definitions in this file are common to all processor types
28    running Darwin, which is the kernel for Mac OS X.  Darwin is
29    basically a BSD user layer laid over a Mach kernel, then evolved
30    for many years (at NeXT) in parallel with other Unix systems.  So
31    while the runtime is a somewhat idiosyncratic Mach-based thing,
32    other definitions look like they would for a BSD variant.  */
33
34 /* Although NeXT ran on many different architectures, as of Jan 2001
35    the only supported Darwin targets are PowerPC and x86.  */
36
37 /* One of Darwin's NeXT legacies is the Mach-O format, which is partly
38    like a.out and partly like COFF, with additional features like
39    multi-architecture binary support.  */
40
41 #define OBJECT_FORMAT_MACHO
42
43 /* Don't assume anything about the header files.  */
44 #define NO_IMPLICIT_EXTERN_C
45
46 /* Suppress g++ attempt to link in the math library automatically. */
47 #define MATH_LIBRARY ""
48
49 /* We have atexit.  */
50
51 #define HAVE_ATEXIT
52
53 /* Define an empty body for the function do_global_dtors() in libgcc2.c.  */
54
55 #define DO_GLOBAL_DTORS_BODY
56
57 /* The string value for __SIZE_TYPE__.  */
58
59 #ifndef SIZE_TYPE
60 #define SIZE_TYPE "long unsigned int"
61 #endif
62
63 /* Type used for ptrdiff_t, as a string used in a declaration.  */
64
65 #undef  PTRDIFF_TYPE
66 #define PTRDIFF_TYPE "int"
67
68 /* wchar_t is int.  */
69
70 #undef  WCHAR_TYPE
71 #define WCHAR_TYPE "int"
72 #undef  WCHAR_TYPE_SIZE
73 #define WCHAR_TYPE_SIZE 32
74
75 /* Default to using the NeXT-style runtime, since that's what is
76    pre-installed on Darwin systems.  */
77
78 #define NEXT_OBJC_RUNTIME
79
80 /* Don't default to pcc-struct-return, because gcc is the only compiler, and
81    we want to retain compatibility with older gcc versions.  */
82
83 #undef  DEFAULT_PCC_STRUCT_RETURN
84 #define DEFAULT_PCC_STRUCT_RETURN 0
85
86 /* True if pragma ms_struct is in effect.  */
87 extern GTY(()) int darwin_ms_struct;
88
89 /* This table intercepts weirdo options whose names would interfere
90    with normal driver conventions, and either translates them into
91    standardly-named options, or adds a 'Z' so that they can get to
92    specs processing without interference.
93
94    Do not expand a linker option to "-Xlinker -<option>", since that
95    forfeits the ability to control via spec strings later.  However,
96    as a special exception, do this translation with -filelist, because
97    otherwise the driver will think there are no input files and quit.
98    (The alternative would be to hack the driver to recognize -filelist
99    specially, but it's simpler to use the translation table.)
100
101    Note that an option name with a prefix that matches another option
102    name, that also takes an argument, needs to be modified so the
103    prefix is different, otherwise a '*' after the shorter option will
104    match with the longer one.
105
106    The SUBTARGET_OPTION_TRANSLATE_TABLE macro, which _must_ be defined
107    in gcc/config/{i386,rs6000}/darwin.h, should contain any additional
108    command-line option translations specific to the particular target
109    architecture.  */
110
111 #define TARGET_OPTION_TRANSLATE_TABLE \
112   { "-all_load", "-Zall_load" },  \
113   { "-allowable_client", "-Zallowable_client" },  \
114   { "-arch_errors_fatal", "-Zarch_errors_fatal" },  \
115   { "-bind_at_load", "-Zbind_at_load" },  \
116   { "-bundle", "-Zbundle" },  \
117   { "-bundle_loader", "-Zbundle_loader" },  \
118   { "-weak_reference_mismatches", "-Zweak_reference_mismatches" },  \
119   { "-dead_strip", "-Zdead_strip" }, \
120   { "-no_dead_strip_inits_and_terms", "-Zno_dead_strip_inits_and_terms" }, \
121   { "-dependency-file", "-MF" }, \
122   { "-dylib_file", "-Zdylib_file" }, \
123   { "-dynamic", "-Zdynamic" },  \
124   { "-dynamiclib", "-Zdynamiclib" },  \
125   { "-exported_symbols_list", "-Zexported_symbols_list" },  \
126   { "-gfull", "-g -fno-eliminate-unused-debug-symbols" }, \
127   { "-gused", "-g -feliminate-unused-debug-symbols" }, \
128   { "-segaddr", "-Zsegaddr" }, \
129   { "-segs_read_only_addr", "-Zsegs_read_only_addr" }, \
130   { "-segs_read_write_addr", "-Zsegs_read_write_addr" }, \
131   { "-seg_addr_table", "-Zseg_addr_table" }, \
132   { "-seg_addr_table_filename", "-Zfn_seg_addr_table_filename" }, \
133   { "-fapple-kext", "-fapple-kext -static -Wa,-static" }, \
134   { "-filelist", "-Xlinker -filelist -Xlinker" },  \
135   { "-findirect-virtual-calls", "-fapple-kext" }, \
136   { "-flat_namespace", "-Zflat_namespace" },  \
137   { "-force_cpusubtype_ALL", "-Zforce_cpusubtype_ALL" },  \
138   { "-force_flat_namespace", "-Zforce_flat_namespace" },  \
139   { "-framework", "-Xlinker -framework -Xlinker" },  \
140   { "-fterminated-vtables", "-fapple-kext" }, \
141   { "-image_base", "-Zimage_base" },  \
142   { "-init", "-Zinit" },  \
143   { "-install_name", "-Zinstall_name" },  \
144   { "-mkernel", "-mkernel -static -Wa,-static" }, \
145   { "-multiply_defined_unused", "-Zmultiplydefinedunused" },  \
146   { "-multiply_defined", "-Zmultiply_defined" },  \
147   { "-multi_module", "-Zmulti_module" },  \
148   { "-static", "-static -Wa,-static" },  \
149   { "-single_module", "-Zsingle_module" },  \
150   { "-unexported_symbols_list", "-Zunexported_symbols_list" }, \
151   SUBTARGET_OPTION_TRANSLATE_TABLE
152
153 #define SUBSUBTARGET_OVERRIDE_OPTIONS                                   \
154   do {                                                                  \
155     darwin_override_options ();                                         \
156   } while (0)
157
158 /* These compiler options take n arguments.  */
159
160 #undef  WORD_SWITCH_TAKES_ARG
161 #define WORD_SWITCH_TAKES_ARG(STR)              \
162   (DEFAULT_WORD_SWITCH_TAKES_ARG (STR) ? 1 :    \
163    !strcmp (STR, "Zallowable_client") ? 1 :     \
164    !strcmp (STR, "arch") ? 1 :                  \
165    !strcmp (STR, "arch_only") ? 1 :             \
166    !strcmp (STR, "Zbundle_loader") ? 1 :        \
167    !strcmp (STR, "client_name") ? 1 :           \
168    !strcmp (STR, "compatibility_version") ? 1 : \
169    !strcmp (STR, "current_version") ? 1 :       \
170    !strcmp (STR, "Zdylib_file") ? 1 :           \
171    !strcmp (STR, "Zexported_symbols_list") ? 1 : \
172    !strcmp (STR, "Zimage_base") ? 1 :           \
173    !strcmp (STR, "Zinit") ? 1 :                 \
174    !strcmp (STR, "Zinstall_name") ? 1 :         \
175    !strcmp (STR, "Zmultiplydefinedunused") ? 1 : \
176    !strcmp (STR, "Zmultiply_defined") ? 1 :     \
177    !strcmp (STR, "precomp-trustfile") ? 1 :     \
178    !strcmp (STR, "read_only_relocs") ? 1 :      \
179    !strcmp (STR, "sectcreate") ? 3 :            \
180    !strcmp (STR, "sectorder") ? 3 :             \
181    !strcmp (STR, "Zsegaddr") ? 2 :              \
182    !strcmp (STR, "Zsegs_read_only_addr") ? 1 :  \
183    !strcmp (STR, "Zsegs_read_write_addr") ? 1 : \
184    !strcmp (STR, "Zseg_addr_table") ? 1 :       \
185    !strcmp (STR, "Zfn_seg_addr_table_filename") ? 1 :\
186    !strcmp (STR, "seg1addr") ? 1 :              \
187    !strcmp (STR, "segprot") ? 3 :               \
188    !strcmp (STR, "sub_library") ? 1 :           \
189    !strcmp (STR, "sub_umbrella") ? 1 :          \
190    !strcmp (STR, "umbrella") ? 1 :              \
191    !strcmp (STR, "undefined") ? 1 :             \
192    !strcmp (STR, "Zunexported_symbols_list") ? 1 : \
193    !strcmp (STR, "Zweak_reference_mismatches") ? 1 : \
194    !strcmp (STR, "pagezero_size") ? 1 :         \
195    !strcmp (STR, "segs_read_only_addr") ? 1 :   \
196    !strcmp (STR, "segs_read_write_addr") ? 1 :  \
197    !strcmp (STR, "sectalign") ? 3 :             \
198    !strcmp (STR, "sectobjectsymbols") ? 2 :     \
199    !strcmp (STR, "segcreate") ? 3 :             \
200    !strcmp (STR, "dylinker_install_name") ? 1 : \
201    0)
202
203 #define SUBTARGET_C_COMMON_OVERRIDE_OPTIONS do {                        \
204     if (flag_mkernel || flag_apple_kext)                                \
205       {                                                                 \
206         if (flag_use_cxa_atexit == 2)                                   \
207           flag_use_cxa_atexit = 0;                                      \
208         /* kexts should always be built without the coalesced sections  \
209            because the kernel loader doesn't grok such sections.  */    \
210         flag_weak = 0;                                                  \
211         /* No RTTI in kexts.  */                                        \
212         flag_rtti = 0;                                                  \
213       }                                                                 \
214   } while (0)
215
216 /* Machine dependent cpp options.  Don't add more options here, add
217    them to darwin_cpp_builtins in darwin-c.c.  */
218
219 #undef  CPP_SPEC
220 #define CPP_SPEC "%{static:%{!dynamic:-D__STATIC__}}%{!static:-D__DYNAMIC__}" \
221         " %{pthread:-D_REENTRANT}"
222
223 /* This is mostly a clone of the standard LINK_COMMAND_SPEC, plus
224    precomp, libtool, and fat build additions.  Also we
225    don't specify a second %G after %L because libSystem is
226    self-contained and doesn't need to link against libgcc.a.  */
227 /* In general, random Darwin linker flags should go into LINK_SPEC
228    instead of LINK_COMMAND_SPEC.  The command spec is better for
229    specifying the handling of options understood by generic Unix
230    linkers, and for positional arguments like libraries.  */
231 #define LINK_COMMAND_SPEC "\
232 %{!fdump=*:%{!fsyntax-only:%{!c:%{!M:%{!MM:%{!E:%{!S:\
233     %(linker) %l %X %{d} %{s} %{t} %{Z} \
234     %{A} %{e*} %{m} %{r} %{x} \
235     %{o*}%{!o:-o a.out} \
236     %{!A:%{!nostdlib:%{!nostartfiles:%S}}} \
237     %{L*} %{fopenmp:%:include(libgomp.spec)%(link_gomp)}   \
238     %(link_libgcc) %o %{fprofile-arcs|fprofile-generate|coverage:-lgcov} \
239     %{!nostdlib:%{!nodefaultlibs:%(link_ssp) %G %L}} \
240     %{!A:%{!nostdlib:%{!nostartfiles:%E}}} %{T*} %{F*} }}}}}}}\n\
241 %{!fdump=*:%{!fsyntax-only:%{!c:%{!M:%{!MM:%{!E:%{!S:\
242     %{.c|.cc|.C|.cpp|.c++|.CPP|.m|.mm: \
243     %{gdwarf-2:%{!gstabs*:%{!gnone: dsymutil %{o*:%*}%{!o:a.out}}}}}}}}}}}}"
244
245 #ifdef TARGET_SYSTEM_ROOT
246 #define LINK_SYSROOT_SPEC \
247   "%{isysroot*:-syslibroot %*;:-syslibroot " TARGET_SYSTEM_ROOT "}"
248 #else
249 #define LINK_SYSROOT_SPEC "%{isysroot*:-syslibroot %*}"
250 #endif
251
252 /* Please keep the random linker options in alphabetical order (modulo
253    'Z' and 'no' prefixes). Note that options taking arguments may appear
254    multiple times on a command line with different arguments each time,
255    so put a * after their names so all of them get passed.  */
256 #define LINK_SPEC  \
257   "%{static}%{!static:-dynamic} \
258    %{fgnu-runtime:%:replace-outfile(-lobjc -lobjc-gnu)}\
259    %{!Zdynamiclib: \
260      %{Zforce_cpusubtype_ALL:-arch %(darwin_arch) -force_cpusubtype_ALL} \
261      %{!Zforce_cpusubtype_ALL:-arch %(darwin_subarch)} \
262      %{Zbundle:-bundle} \
263      %{Zbundle_loader*:-bundle_loader %*} \
264      %{client_name*} \
265      %{compatibility_version*:%e-compatibility_version only allowed with -dynamiclib\
266 } \
267      %{current_version*:%e-current_version only allowed with -dynamiclib} \
268      %{Zforce_flat_namespace:-force_flat_namespace} \
269      %{Zinstall_name*:%e-install_name only allowed with -dynamiclib} \
270      %{keep_private_externs} \
271      %{private_bundle} \
272     } \
273    %{Zdynamiclib: -dylib \
274      %{Zbundle:%e-bundle not allowed with -dynamiclib} \
275      %{Zbundle_loader*:%e-bundle_loader not allowed with -dynamiclib} \
276      %{client_name*:%e-client_name not allowed with -dynamiclib} \
277      %{compatibility_version*:-dylib_compatibility_version %*} \
278      %{current_version*:-dylib_current_version %*} \
279      %{Zforce_cpusubtype_ALL:-arch %(darwin_arch)} \
280      %{!Zforce_cpusubtype_ALL: -arch %(darwin_subarch)} \
281      %{Zforce_flat_namespace:%e-force_flat_namespace not allowed with -dynamiclib} \
282      %{Zinstall_name*:-dylib_install_name %*} \
283      %{keep_private_externs:%e-keep_private_externs not allowed with -dynamiclib} \
284      %{private_bundle:%e-private_bundle not allowed with -dynamiclib} \
285     } \
286    %{Zall_load:-all_load} \
287    %{Zallowable_client*:-allowable_client %*} \
288    %{Zbind_at_load:-bind_at_load} \
289    %{Zarch_errors_fatal:-arch_errors_fatal} \
290    %{Zdead_strip:-dead_strip} \
291    %{Zno_dead_strip_inits_and_terms:-no_dead_strip_inits_and_terms} \
292    %{Zdylib_file*:-dylib_file %*} \
293    %{Zdynamic:-dynamic}\
294    %{Zexported_symbols_list*:-exported_symbols_list %*} \
295    %{Zflat_namespace:-flat_namespace} \
296    %{headerpad_max_install_names*} \
297    %{Zimage_base*:-image_base %*} \
298    %{Zinit*:-init %*} \
299    %{mmacosx-version-min=*:-macosx_version_min %*} \
300    %{!mmacosx-version-min=*:%{shared-libgcc:-macosx_version_min 10.3}} \
301    %{nomultidefs} \
302    %{Zmulti_module:-multi_module} %{Zsingle_module:-single_module} \
303    %{Zmultiply_defined*:-multiply_defined %*} \
304    %{!Zmultiply_defined*:%{shared-libgcc: \
305      %:version-compare(< 10.5 mmacosx-version-min= -multiply_defined) \
306      %:version-compare(< 10.5 mmacosx-version-min= suppress)}} \
307    %{Zmultiplydefinedunused*:-multiply_defined_unused %*} \
308    %{prebind} %{noprebind} %{nofixprebinding} %{prebind_all_twolevel_modules} \
309    %{read_only_relocs} \
310    %{sectcreate*} %{sectorder*} %{seg1addr*} %{segprot*} \
311    %{Zsegaddr*:-segaddr %*} \
312    %{Zsegs_read_only_addr*:-segs_read_only_addr %*} \
313    %{Zsegs_read_write_addr*:-segs_read_write_addr %*} \
314    %{Zseg_addr_table*: -seg_addr_table %*} \
315    %{Zfn_seg_addr_table_filename*:-seg_addr_table_filename %*} \
316    %{sub_library*} %{sub_umbrella*} \
317    " LINK_SYSROOT_SPEC " \
318    %{twolevel_namespace} %{twolevel_namespace_hints} \
319    %{umbrella*} \
320    %{undefined*} \
321    %{Zunexported_symbols_list*:-unexported_symbols_list %*} \
322    %{Zweak_reference_mismatches*:-weak_reference_mismatches %*} \
323    %{!Zweak_reference_mismatches*:-weak_reference_mismatches non-weak} \
324    %{X} \
325    %{y*} \
326    %{w} \
327    %{pagezero_size*} %{segs_read_*} %{seglinkedit} %{noseglinkedit}  \
328    %{sectalign*} %{sectobjectsymbols*} %{segcreate*} %{whyload} \
329    %{whatsloaded} %{dylinker_install_name*} \
330    %{dylinker} %{Mach} "
331
332
333 /* Machine dependent libraries.  */
334
335 #define LIB_SPEC "%{!static:-lSystem}"
336
337 /* Support -mmacosx-version-min by supplying different (stub) libgcc_s.dylib
338    libraries to link against, and by not linking against libgcc_s on
339    earlier-than-10.3.9.
340
341    Note that by default, -lgcc_eh is not linked against!  This is
342    because in a future version of Darwin the EH frame information may
343    be in a new format, or the fallback routine might be changed; if
344    you want to explicitly link against the static version of those
345    routines, because you know you don't need to unwind through system
346    libraries, you need to explicitly say -static-libgcc.
347
348    If it is linked against, it has to be before -lgcc, because it may
349    need symbols from -lgcc.  */
350 #undef REAL_LIBGCC_SPEC
351 #define REAL_LIBGCC_SPEC                                                   \
352    "%{static-libgcc|static: -lgcc_eh -lgcc;                                \
353       shared-libgcc|fexceptions:                                           \
354        %:version-compare(!> 10.5 mmacosx-version-min= -lgcc_s.10.4)        \
355        %:version-compare(>= 10.5 mmacosx-version-min= -lgcc_s.10.5)        \
356        -lgcc;                                                              \
357       :%:version-compare(>< 10.3.9 10.5 mmacosx-version-min= -lgcc_s.10.4) \
358        %:version-compare(>= 10.5 mmacosx-version-min= -lgcc_s.10.5)        \
359        -lgcc}"
360
361 /* We specify crt0.o as -lcrt0.o so that ld will search the library path.
362
363    crt3.o provides __cxa_atexit on systems that don't have it.  Since
364    it's only used with C++, which requires passing -shared-libgcc, key
365    off that to avoid unnecessarily adding a destructor to every
366    powerpc program built.  */
367
368 #undef  STARTFILE_SPEC
369 #define STARTFILE_SPEC                                                      \
370   "%{Zdynamiclib: %(darwin_dylib1) }                                        \
371    %{!Zdynamiclib:%{Zbundle:%{!static:-lbundle1.o}}                         \
372      %{!Zbundle:%{pg:%{static:-lgcrt0.o}                                    \
373                      %{!static:%{object:-lgcrt0.o}                          \
374                                %{!object:%{preload:-lgcrt0.o}               \
375                                  %{!preload:-lgcrt1.o %(darwin_crt2)}}}}    \
376                 %{!pg:%{static:-lcrt0.o}                                    \
377                       %{!static:%{object:-lcrt0.o}                          \
378                                 %{!object:%{preload:-lcrt0.o}               \
379                                   %{!preload: %(darwin_crt1)  %(darwin_crt2)}}}}}}  \
380   %{shared-libgcc:%:version-compare(< 10.5 mmacosx-version-min= crt3.o%s)}"
381
382 /* The native Darwin linker doesn't necessarily place files in the order
383    that they're specified on the link line.  Thus, it is pointless
384    to put anything in ENDFILE_SPEC.  */
385 /* #define ENDFILE_SPEC "" */
386
387 #define DARWIN_EXTRA_SPECS     \
388   { "darwin_crt1", DARWIN_CRT1_SPEC },                                 \
389   { "darwin_dylib1", DARWIN_DYLIB1_SPEC },
390
391 #define DARWIN_DYLIB1_SPEC                                             \
392   "%:version-compare(!> 10.5 mmacosx-version-min= -ldylib1.o)          \
393    %:version-compare(>= 10.5 mmacosx-version-min= -ldylib1.10.5.o)"
394
395 #define DARWIN_CRT1_SPEC                                               \
396   "%:version-compare(!> 10.5 mmacosx-version-min= -lcrt1.o)            \
397    %:version-compare(>= 10.5 mmacosx-version-min= -lcrt1.10.5.o)"
398
399 /* Default Darwin ASM_SPEC, very simple.  */
400 #define ASM_SPEC "-arch %(darwin_arch) \
401   %{Zforce_cpusubtype_ALL:-force_cpusubtype_ALL}"
402
403 /* We still allow output of STABS.  */
404
405 #define DBX_DEBUGGING_INFO 1
406
407 #define DWARF2_DEBUGGING_INFO
408 #define PREFERRED_DEBUGGING_TYPE DBX_DEBUG
409
410 #define DEBUG_FRAME_SECTION     "__DWARF,__debug_frame,regular,debug"
411 #define DEBUG_INFO_SECTION      "__DWARF,__debug_info,regular,debug"
412 #define DEBUG_ABBREV_SECTION    "__DWARF,__debug_abbrev,regular,debug"
413 #define DEBUG_ARANGES_SECTION   "__DWARF,__debug_aranges,regular,debug"
414 #define DEBUG_MACINFO_SECTION   "__DWARF,__debug_macinfo,regular,debug"
415 #define DEBUG_LINE_SECTION      "__DWARF,__debug_line,regular,debug"
416 #define DEBUG_LOC_SECTION       "__DWARF,__debug_loc,regular,debug"
417 #define DEBUG_PUBNAMES_SECTION  "__DWARF,__debug_pubnames,regular,debug"
418 #define DEBUG_PUBTYPES_SECTION  "__DWARF,__debug_pubtypes,regular,debug"
419 #define DEBUG_STR_SECTION       "__DWARF,__debug_str,regular,debug"
420 #define DEBUG_RANGES_SECTION    "__DWARF,__debug_ranges,regular,debug"
421
422 /* When generating stabs debugging, use N_BINCL entries.  */
423
424 #define DBX_USE_BINCL
425
426 /* There is no limit to the length of stabs strings.  */
427
428 #define DBX_CONTIN_LENGTH 0
429
430 /* gdb needs a null N_SO at the end of each file for scattered loading.  */
431
432 #define DBX_OUTPUT_NULL_N_SO_AT_MAIN_SOURCE_FILE_END
433
434 /* GCC's definition of 'one_only' is the same as its definition of 'weak'.  */
435 #define MAKE_DECL_ONE_ONLY(DECL) (DECL_WEAK (DECL) = 1)
436
437 /* Mach-O supports 'weak imports', and 'weak definitions' in coalesced
438    sections.  machopic_select_section ensures that weak variables go in
439    coalesced sections.  Weak aliases (or any other kind of aliases) are
440    not supported.  Weak symbols that aren't visible outside the .s file
441    are not supported.  */
442 #define ASM_WEAKEN_DECL(FILE, DECL, NAME, ALIAS)                        \
443   do {                                                                  \
444     if (ALIAS)                                                          \
445       {                                                                 \
446         warning (0, "alias definitions not supported in Mach-O; ignored");      \
447         break;                                                          \
448       }                                                                 \
449                                                                         \
450     if (! DECL_EXTERNAL (DECL) && TREE_PUBLIC (DECL))                   \
451       targetm.asm_out.globalize_label (FILE, NAME);                     \
452     if (DECL_EXTERNAL (DECL))                                           \
453       fputs ("\t.weak_reference ", FILE);                               \
454     else if (! lookup_attribute ("weak", DECL_ATTRIBUTES (DECL))        \
455         && lookup_attribute ("weak_import", DECL_ATTRIBUTES (DECL)))    \
456       break;                                                            \
457     else if (TREE_PUBLIC (DECL))                                        \
458       fputs ("\t.weak_definition ", FILE);                              \
459     else                                                                \
460       break;                                                            \
461     assemble_name (FILE, NAME);                                         \
462     fputc ('\n', FILE);                                                 \
463   } while (0)
464
465 /* Darwin has the pthread routines in libSystem, which every program
466    links to, so there's no need for weak-ness for that.  */
467 #define GTHREAD_USE_WEAK 0
468
469 /* The Darwin linker imposes two limitations on common symbols: they
470    can't have hidden visibility, and they can't appear in dylibs.  As
471    a consequence, we should never use common symbols to represent
472    vague linkage. */
473 #undef USE_COMMON_FOR_ONE_ONLY
474 #define USE_COMMON_FOR_ONE_ONLY 0
475
476 /* The Darwin linker doesn't want coalesced symbols to appear in
477    a static archive's table of contents. */
478 #undef TARGET_WEAK_NOT_IN_ARCHIVE_TOC
479 #define TARGET_WEAK_NOT_IN_ARCHIVE_TOC 1
480
481 /* On Darwin, we don't (at the time of writing) have linkonce sections
482    with names, so it's safe to make the class data not comdat.  */
483 #define TARGET_CXX_CLASS_DATA_ALWAYS_COMDAT hook_bool_void_false
484
485 /* We make exception information linkonce. */
486 #undef TARGET_USES_WEAK_UNWIND_INFO
487 #define TARGET_USES_WEAK_UNWIND_INFO 1
488
489 /* We need to use a nonlocal label for the start of an EH frame: the
490    Darwin linker requires that a coalesced section start with a label.
491    Unfortunately, it also requires that 'debug' sections don't contain
492    labels.  */
493 #undef FRAME_BEGIN_LABEL
494 #define FRAME_BEGIN_LABEL (for_eh ? "EH_frame" : "Lframe")
495
496 /* Emit a label for the FDE corresponding to DECL.  EMPTY means
497    emit a label for an empty FDE. */
498 #define TARGET_ASM_EMIT_UNWIND_LABEL darwin_emit_unwind_label
499
500 /* Emit a label to separate the exception table.  */
501 #define TARGET_ASM_EMIT_EXCEPT_TABLE_LABEL darwin_emit_except_table_label
502
503 /* Our profiling scheme doesn't LP labels and counter words.  */
504
505 #define NO_PROFILE_COUNTERS     1
506
507 #undef  INIT_SECTION_ASM_OP
508 #define INIT_SECTION_ASM_OP
509
510 #undef  INVOKE__main
511
512 #define TARGET_ASM_CONSTRUCTOR  machopic_asm_out_constructor
513 #define TARGET_ASM_DESTRUCTOR   machopic_asm_out_destructor
514
515 /* Always prefix with an underscore.  */
516
517 #define USER_LABEL_PREFIX "_"
518
519 /* Don't output a .file directive.  That is only used by the assembler for
520    error reporting.  */
521 #undef  TARGET_ASM_FILE_START_FILE_DIRECTIVE
522 #define TARGET_ASM_FILE_START_FILE_DIRECTIVE false
523
524 #undef  TARGET_ASM_FILE_END
525 #define TARGET_ASM_FILE_END darwin_file_end
526
527 #define ASM_OUTPUT_SKIP(FILE,SIZE)  \
528   fprintf (FILE, "\t.space "HOST_WIDE_INT_PRINT_UNSIGNED"\n", SIZE)
529
530 /* Give ObjC methods pretty symbol names.  */
531
532 #undef  OBJC_GEN_METHOD_LABEL
533 #define OBJC_GEN_METHOD_LABEL(BUF,IS_INST,CLASS_NAME,CAT_NAME,SEL_NAME,NUM) \
534   do { if (CAT_NAME)                                                    \
535          sprintf (BUF, "%c[%s(%s) %s]", (IS_INST) ? '-' : '+',          \
536                   (CLASS_NAME), (CAT_NAME), (SEL_NAME));                \
537        else                                                             \
538          sprintf (BUF, "%c[%s %s]", (IS_INST) ? '-' : '+',              \
539                   (CLASS_NAME), (SEL_NAME));                            \
540      } while (0)
541
542 /* The RTTI data (e.g., __ti4name) is common and public (and static),
543    but it does need to be referenced via indirect PIC data pointers.
544    The machopic_define_symbol calls are telling the machopic subsystem
545    that the name *is* defined in this module, so it doesn't need to
546    make them indirect.  */
547
548 #undef ASM_DECLARE_OBJECT_NAME
549 #define ASM_DECLARE_OBJECT_NAME(FILE, NAME, DECL)                       \
550   do {                                                                  \
551     const char *xname = NAME;                                           \
552     if (GET_CODE (XEXP (DECL_RTL (DECL), 0)) != SYMBOL_REF)             \
553       xname = IDENTIFIER_POINTER (DECL_NAME (DECL));                    \
554     if (! DECL_WEAK (DECL)                                              \
555         && ((TREE_STATIC (DECL)                                         \
556              && (!DECL_COMMON (DECL) || !TREE_PUBLIC (DECL)))           \
557             || DECL_INITIAL (DECL)))                                    \
558         machopic_define_symbol (DECL_RTL (DECL));                       \
559     if ((TREE_STATIC (DECL)                                             \
560          && (!DECL_COMMON (DECL) || !TREE_PUBLIC (DECL)))               \
561         || DECL_INITIAL (DECL))                                         \
562       (* targetm.encode_section_info) (DECL, DECL_RTL (DECL), false);   \
563     ASM_OUTPUT_LABEL (FILE, xname);                                     \
564     /* Darwin doesn't support zero-size objects, so give them a         \
565        byte.  */                                                        \
566     if (tree_low_cst (DECL_SIZE_UNIT (DECL), 1) == 0)                   \
567       assemble_zeros (1);                                               \
568   } while (0)
569
570 #define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL)                     \
571   do {                                                                  \
572     const char *xname = NAME;                                           \
573     if (GET_CODE (XEXP (DECL_RTL (DECL), 0)) != SYMBOL_REF)             \
574       xname = IDENTIFIER_POINTER (DECL_NAME (DECL));                    \
575     if (! DECL_WEAK (DECL)                                              \
576         && ((TREE_STATIC (DECL)                                         \
577              && (!DECL_COMMON (DECL) || !TREE_PUBLIC (DECL)))           \
578             || DECL_INITIAL (DECL)))                                    \
579         machopic_define_symbol (DECL_RTL (DECL));                       \
580     if ((TREE_STATIC (DECL)                                             \
581          && (!DECL_COMMON (DECL) || !TREE_PUBLIC (DECL)))               \
582         || DECL_INITIAL (DECL))                                         \
583       (* targetm.encode_section_info) (DECL, DECL_RTL (DECL), false);   \
584     ASM_OUTPUT_LABEL (FILE, xname);                                     \
585   } while (0)
586
587 #define ASM_DECLARE_CONSTANT_NAME(FILE, NAME, EXP, SIZE)        \
588   do {                                                          \
589     ASM_OUTPUT_LABEL (FILE, NAME);                              \
590     /* Darwin doesn't support zero-size objects, so give them a \
591        byte.  */                                                \
592     if ((SIZE) == 0)                                            \
593       assemble_zeros (1);                                       \
594   } while (0)
595
596 /* Wrap new method names in quotes so the assembler doesn't gag.
597    Make Objective-C internal symbols local.  */
598
599 #undef  ASM_OUTPUT_LABELREF
600 #define ASM_OUTPUT_LABELREF(FILE,NAME)                                       \
601   do {                                                                       \
602        const char *xname = (NAME);                                           \
603        if (! strcmp (xname, "<pic base>"))                                   \
604          machopic_output_function_base_name(FILE);                           \
605        else if (xname[0] == '&' || xname[0] == '*')                          \
606          {                                                                   \
607            int len = strlen (xname);                                         \
608            if (len > 6 && !strcmp ("$stub", xname + len - 5))                \
609              machopic_validate_stub_or_non_lazy_ptr (xname);                 \
610            else if (len > 7 && !strcmp ("$stub\"", xname + len - 6))         \
611              machopic_validate_stub_or_non_lazy_ptr (xname);                 \
612            else if (len > 14 && !strcmp ("$non_lazy_ptr", xname + len - 13)) \
613              machopic_validate_stub_or_non_lazy_ptr (xname);                 \
614            else if (len > 15 && !strcmp ("$non_lazy_ptr\"", xname + len - 14)) \
615              machopic_validate_stub_or_non_lazy_ptr (xname);                 \
616            if (xname[1] != '"' && name_needs_quotes (&xname[1]))             \
617              fprintf (FILE, "\"%s\"", &xname[1]);                            \
618            else                                                              \
619              fputs (&xname[1], FILE);                                        \
620          }                                                                   \
621        else if (xname[0] == '+' || xname[0] == '-')                          \
622          fprintf (FILE, "\"%s\"", xname);                                    \
623        else if (!strncmp (xname, "_OBJC_", 6))                               \
624          fprintf (FILE, "L%s", xname);                                       \
625        else if (!strncmp (xname, ".objc_class_name_", 17))                   \
626          fprintf (FILE, "%s", xname);                                        \
627        else if (xname[0] != '"' && name_needs_quotes (xname))                \
628          fprintf (FILE, "\"%s\"", xname);                                    \
629        else                                                                  \
630          asm_fprintf (FILE, "%U%s", xname);                                  \
631   } while (0)
632
633 /* Output before executable code.  */
634 #undef TEXT_SECTION_ASM_OP
635 #define TEXT_SECTION_ASM_OP "\t.text"
636
637 /* Output before writable data.  */
638
639 #undef DATA_SECTION_ASM_OP
640 #define DATA_SECTION_ASM_OP "\t.data"
641
642 #undef  ALIGN_ASM_OP
643 #define ALIGN_ASM_OP            ".align"
644
645 #undef  ASM_OUTPUT_ALIGN
646 #define ASM_OUTPUT_ALIGN(FILE,LOG)      \
647   if ((LOG) != 0)                       \
648     fprintf (FILE, "\t%s %d\n", ALIGN_ASM_OP, (LOG))
649
650 /* Ensure correct alignment of bss data.  */
651
652 #undef  ASM_OUTPUT_ALIGNED_DECL_LOCAL
653 #define ASM_OUTPUT_ALIGNED_DECL_LOCAL(FILE, DECL, NAME, SIZE, ALIGN)    \
654   do {                                                                  \
655     unsigned HOST_WIDE_INT _new_size = SIZE;                            \
656     fputs (".lcomm ", (FILE));                                          \
657     assemble_name ((FILE), (NAME));                                     \
658     if (_new_size == 0) _new_size = 1;                                  \
659     fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%u\n", _new_size, \
660              floor_log2 ((ALIGN) / BITS_PER_UNIT));                     \
661     if ((DECL) && ((TREE_STATIC (DECL)                                  \
662          && (!DECL_COMMON (DECL) || !TREE_PUBLIC (DECL)))               \
663         || DECL_INITIAL (DECL)))                                        \
664       {                                                                 \
665         (* targetm.encode_section_info) (DECL, DECL_RTL (DECL), false); \
666         machopic_define_symbol (DECL_RTL (DECL));                       \
667       }                                                                 \
668   } while (0)
669
670 /* The maximum alignment which the object file format can support.
671    For Mach-O, this is 2^15.  */
672
673 #undef  MAX_OFILE_ALIGNMENT
674 #define MAX_OFILE_ALIGNMENT 0x8000
675
676 /* Declare the section variables.  */
677 #ifndef USED_FOR_TARGET
678 enum darwin_section_enum {
679 #define DEF_SECTION(NAME, FLAGS, DIRECTIVE, OBJC) NAME,
680 #include "darwin-sections.def"
681 #undef DEF_SECTION
682   NUM_DARWIN_SECTIONS
683 };
684 extern GTY(()) section * darwin_sections[NUM_DARWIN_SECTIONS];
685 #endif
686
687 #undef  TARGET_ASM_SELECT_SECTION
688 #define TARGET_ASM_SELECT_SECTION machopic_select_section
689 #define USE_SELECT_SECTION_FOR_FUNCTIONS
690
691 #undef  TARGET_ASM_SELECT_RTX_SECTION
692 #define TARGET_ASM_SELECT_RTX_SECTION machopic_select_rtx_section
693 #undef  TARGET_ASM_UNIQUE_SECTION
694 #define TARGET_ASM_UNIQUE_SECTION darwin_unique_section
695 #undef  TARGET_ASM_FUNCTION_RODATA_SECTION
696 #define TARGET_ASM_FUNCTION_RODATA_SECTION default_no_function_rodata_section
697
698
699 #define ASM_DECLARE_UNRESOLVED_REFERENCE(FILE,NAME)                     \
700     do {                                                                \
701          if (FILE) {                                                    \
702            if (MACHOPIC_INDIRECT)                                       \
703              fprintf (FILE, "\t.lazy_reference ");                      \
704            else                                                         \
705              fprintf (FILE, "\t.reference ");                           \
706            assemble_name (FILE, NAME);                                  \
707            fprintf (FILE, "\n");                                        \
708          }                                                              \
709        } while (0)
710
711 #define ASM_DECLARE_CLASS_REFERENCE(FILE,NAME)                          \
712     do {                                                                \
713          if (FILE) {                                                    \
714            fprintf (FILE, "\t");                                        \
715            assemble_name (FILE, NAME);                                  \
716            fprintf (FILE, "=0\n");                                      \
717            (*targetm.asm_out.globalize_label) (FILE, NAME);             \
718          }                                                              \
719        } while (0)
720
721 /* Globalizing directive for a label.  */
722 #define GLOBAL_ASM_OP ".globl "
723 #define TARGET_ASM_GLOBALIZE_LABEL darwin_globalize_label
724
725 /* Emit an assembler directive to set visibility for a symbol.  Used
726    to support visibility attribute and Darwin's private extern
727    feature.  */
728 #undef TARGET_ASM_ASSEMBLE_VISIBILITY
729 #define TARGET_ASM_ASSEMBLE_VISIBILITY darwin_assemble_visibility
730
731 /* Extra attributes for Darwin.  */
732 #define SUBTARGET_ATTRIBUTE_TABLE                                            \
733   /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */ \
734   { "apple_kext_compatibility", 0, 0, false, true, false,                    \
735     darwin_handle_kext_attribute },                                          \
736   { "weak_import", 0, 0, true, false, false,                                 \
737     darwin_handle_weak_import_attribute }
738
739 #undef ASM_GENERATE_INTERNAL_LABEL
740 #define ASM_GENERATE_INTERNAL_LABEL(LABEL,PREFIX,NUM)   \
741   sprintf (LABEL, "*%s%ld", PREFIX, (long)(NUM))
742
743 #undef TARGET_ASM_MARK_DECL_PRESERVED
744 #define TARGET_ASM_MARK_DECL_PRESERVED darwin_mark_decl_preserved
745
746 /* Set on a symbol with SYMBOL_FLAG_FUNCTION or
747    MACHO_SYMBOL_FLAG_VARIABLE to indicate that the function or
748    variable has been defined in this translation unit.
749    When porting Mach-O to new architectures you need to make
750    sure these aren't clobbered by the backend.  */
751
752 #define MACHO_SYMBOL_FLAG_VARIABLE (SYMBOL_FLAG_MACH_DEP)
753 #define MACHO_SYMBOL_FLAG_DEFINED ((SYMBOL_FLAG_MACH_DEP) << 1)
754
755 /* Set on a symbol to indicate when fix-and-continue style code
756    generation is being used and the symbol refers to a static symbol
757    that should be rebound from new instances of a translation unit to
758    the original instance of the data.  */
759
760 #define MACHO_SYMBOL_STATIC ((SYMBOL_FLAG_MACH_DEP) << 2)
761
762 /* Symbolic names for various things we might know about a symbol.  */
763
764 enum machopic_addr_class {
765   MACHOPIC_UNDEFINED,
766   MACHOPIC_DEFINED_DATA,
767   MACHOPIC_UNDEFINED_DATA,
768   MACHOPIC_DEFINED_FUNCTION,
769   MACHOPIC_UNDEFINED_FUNCTION
770 };
771
772 /* Macros defining the various PIC cases.  */
773
774 #define MACHO_DYNAMIC_NO_PIC_P  (TARGET_DYNAMIC_NO_PIC)
775 #define MACHOPIC_INDIRECT       (flag_pic || MACHO_DYNAMIC_NO_PIC_P)
776 #define MACHOPIC_JUST_INDIRECT  (MACHO_DYNAMIC_NO_PIC_P)
777 #define MACHOPIC_PURE           (flag_pic && ! MACHO_DYNAMIC_NO_PIC_P)
778
779 #undef TARGET_ENCODE_SECTION_INFO
780 #define TARGET_ENCODE_SECTION_INFO  darwin_encode_section_info
781 #undef TARGET_STRIP_NAME_ENCODING
782 #define TARGET_STRIP_NAME_ENCODING  default_strip_name_encoding
783
784 #define GEN_BINDER_NAME_FOR_STUB(BUF,STUB,STUB_LENGTH)          \
785   do {                                                          \
786     const char *const stub_ = (STUB);                           \
787     char *buffer_ = (BUF);                                      \
788     strcpy (buffer_, stub_);                                    \
789     if (stub_[0] == '"')                                        \
790       {                                                         \
791         strcpy (buffer_ + (STUB_LENGTH) - 1, "_binder\"");      \
792       }                                                         \
793     else                                                        \
794       {                                                         \
795         strcpy (buffer_ + (STUB_LENGTH), "_binder");            \
796       }                                                         \
797   } while (0)
798
799 #define GEN_SYMBOL_NAME_FOR_SYMBOL(BUF,SYMBOL,SYMBOL_LENGTH)    \
800   do {                                                          \
801     const char *const symbol_ = (SYMBOL);                       \
802     char *buffer_ = (BUF);                                      \
803     if (name_needs_quotes (symbol_) && symbol_[0] != '"')       \
804       {                                                         \
805           sprintf (buffer_, "\"%s\"", symbol_);                 \
806       }                                                         \
807     else                                                        \
808       {                                                         \
809         strcpy (buffer_, symbol_);                              \
810       }                                                         \
811   } while (0)
812
813 /* Given a symbol name string, create the lazy pointer version
814    of the symbol name.  */
815
816 #define GEN_LAZY_PTR_NAME_FOR_SYMBOL(BUF,SYMBOL,SYMBOL_LENGTH)  \
817   do {                                                          \
818     const char *symbol_ = (SYMBOL);                             \
819     char *buffer_ = (BUF);                                      \
820     if (symbol_[0] == '"')                                      \
821       {                                                         \
822         strcpy (buffer_, "\"L");                                \
823         strcpy (buffer_ + 2, symbol_ + 1);                      \
824         strcpy (buffer_ + (SYMBOL_LENGTH), "$lazy_ptr\"");      \
825       }                                                         \
826     else if (name_needs_quotes (symbol_))                       \
827       {                                                         \
828         strcpy (buffer_, "\"L");                                \
829         strcpy (buffer_ + 2, symbol_);                          \
830         strcpy (buffer_ + (SYMBOL_LENGTH) + 2, "$lazy_ptr\"");  \
831       }                                                         \
832     else                                                        \
833       {                                                         \
834         strcpy (buffer_, "L");                                  \
835         strcpy (buffer_ + 1, symbol_);                          \
836         strcpy (buffer_ + (SYMBOL_LENGTH) + 1, "$lazy_ptr");    \
837       }                                                         \
838   } while (0)
839
840 #define EH_FRAME_SECTION_NAME   "__TEXT"
841 #define EH_FRAME_SECTION_ATTR ",coalesced,no_toc+strip_static_syms+live_support"
842
843 /* Java runtime class list.  */
844 #define JCR_SECTION_NAME "__DATA,jcr,regular,no_dead_strip"
845
846 #undef ASM_PREFERRED_EH_DATA_FORMAT
847 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE,GLOBAL)  \
848   (((CODE) == 2 && (GLOBAL) == 1) \
849    ? (DW_EH_PE_pcrel | DW_EH_PE_indirect | DW_EH_PE_sdata4) : \
850      ((CODE) == 1 || (GLOBAL) == 0) ? DW_EH_PE_pcrel : DW_EH_PE_absptr)
851
852 #define ASM_OUTPUT_DWARF_DELTA(FILE,SIZE,LABEL1,LABEL2)  \
853   darwin_asm_output_dwarf_delta (FILE, SIZE, LABEL1, LABEL2)
854
855 #define ASM_OUTPUT_DWARF_OFFSET(FILE,SIZE,LABEL,BASE)  \
856   darwin_asm_output_dwarf_offset (FILE, SIZE, LABEL, BASE)
857
858 #define ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX(ASM_OUT_FILE, ENCODING, SIZE, ADDR, DONE)     \
859       if (ENCODING == ASM_PREFERRED_EH_DATA_FORMAT (2, 1)) {                            \
860         darwin_non_lazy_pcrel (ASM_OUT_FILE, ADDR);                                     \
861         goto DONE;                                                                      \
862       }
863
864 /* Experimentally, putting jump tables in text is faster on SPEC.
865    Also this is needed for correctness for coalesced functions.  */
866
867 #ifndef JUMP_TABLES_IN_TEXT_SECTION
868 #define JUMP_TABLES_IN_TEXT_SECTION 1
869 #endif
870
871 #define TARGET_TERMINATE_DW2_EH_FRAME_INFO false
872
873 #define TARGET_ASM_INIT_SECTIONS darwin_init_sections
874 #undef TARGET_ASM_NAMED_SECTION
875 #define TARGET_ASM_NAMED_SECTION darwin_asm_named_section
876
877 /* Handle pragma weak and pragma pack.  */
878 #define HANDLE_SYSV_PRAGMA 1
879
880 #define HANDLE_PRAGMA_PACK_PUSH_POP 1
881
882 #define DARWIN_REGISTER_TARGET_PRAGMAS()                        \
883   do {                                                          \
884     c_register_pragma (0, "mark", darwin_pragma_ignore);        \
885     c_register_pragma (0, "options", darwin_pragma_options);    \
886     c_register_pragma (0, "segment", darwin_pragma_ignore);     \
887     c_register_pragma (0, "unused", darwin_pragma_unused);      \
888     c_register_pragma (0, "ms_struct", darwin_pragma_ms_struct); \
889   } while (0)
890
891 #undef ASM_APP_ON
892 #define ASM_APP_ON ""
893 #undef ASM_APP_OFF
894 #define ASM_APP_OFF ""
895
896 void darwin_register_frameworks (const char *, const char *, int);
897 void darwin_register_objc_includes (const char *, const char *, int);
898 #define TARGET_EXTRA_PRE_INCLUDES darwin_register_objc_includes
899 #define TARGET_EXTRA_INCLUDES darwin_register_frameworks
900
901 void add_framework_path (char *);
902 #define TARGET_OPTF add_framework_path
903
904 #define TARGET_POSIX_IO
905
906 /* All new versions of Darwin have C99 functions.  */
907
908 #define TARGET_C99_FUNCTIONS 1
909
910 #define WINT_TYPE "int"
911
912 /* Every program on darwin links against libSystem which contains the pthread
913    routines, so there's no need to explicitly call out when doing threaded
914    work.  */
915
916 #undef GOMP_SELF_SPECS
917 #define GOMP_SELF_SPECS ""
918
919 /* Darwin can't support anchors until we can cope with the adjustments
920    to size that ASM_DECLARE_OBJECT_NAME and ASM_DECLARE_CONSTANT_NAME
921    when outputting members of an anchor block and the linker can be
922    taught to keep them together or we find some other suitable
923    code-gen technique.  */
924
925 #if 0
926 #define TARGET_ASM_OUTPUT_ANCHOR darwin_asm_output_anchor
927 #else
928 #define TARGET_ASM_OUTPUT_ANCHOR NULL
929 #endif
930
931 /* Attempt to turn on execute permission for the stack.  This may be
932     used by INITIALIZE_TRAMPOLINE of the target needs it (that is,
933     if the target machine can change execute permissions on a page).
934
935     There is no way to query the execute permission of the stack, so
936     we always issue the mprotect() call.
937
938     Unfortunately it is not possible to make this namespace-clean.
939
940     Also note that no errors should be emitted by this code; it is
941     considered dangerous for library calls to send messages to
942     stdout/stderr.  */
943
944 #define ENABLE_EXECUTE_STACK                                            \
945 extern void __enable_execute_stack (void *);                            \
946 void                                                                    \
947 __enable_execute_stack (void *addr)                                     \
948 {                                                                       \
949    extern int mprotect (void *, size_t, int);                           \
950    extern int getpagesize (void);                                       \
951    static int size;                                                     \
952    static long mask;                                                    \
953                                                                         \
954    char *page, *end;                                                    \
955                                                                         \
956    if (size == 0)                                                       \
957      {                                                                  \
958        size = getpagesize();                                            \
959        mask = ~((long) size - 1);                                       \
960      }                                                                  \
961                                                                         \
962    page = (char *) (((long) addr) & mask);                              \
963    end  = (char *) ((((long) (addr + (TARGET_64BIT ? 48 : 40))) & mask) + size); \
964                                                                         \
965    /* 7 == PROT_READ | PROT_WRITE | PROT_EXEC */                        \
966    (void) mprotect (page, end - page, 7);                               \
967 }
968
969 /* For Apple KEXTs, we make the constructors return this to match gcc
970    2.95.  */
971 #define TARGET_CXX_CDTOR_RETURNS_THIS (darwin_kextabi_p)
972 extern int flag_mkernel;
973 extern int flag_apple_kext;
974 #define TARGET_KEXTABI flag_apple_kext
975
976 #endif /* CONFIG_DARWIN_H */