1 /* Base configuration file for all OpenBSD targets.
2    Copyright (C) 1999-2021 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
9 any later version.
10 
11 GCC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 GNU General Public License for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3.  If not see
18 <http://www.gnu.org/licenses/>.  */
19 
20 /* Common OpenBSD configuration.
21    All OpenBSD architectures include this file, which is intended as
22    a repository for common defines.
23 
24    Some defines are common to all architectures, a few of them are
25    triggered by OBSD_* guards, so that we won't override architecture
26    defaults by mistakes.
27 
28    OBSD_HAS_CORRECT_SPECS:
29       another mechanism provides correct specs already.
30    OBSD_NO_DYNAMIC_LIBRARIES:
31       no implementation of dynamic libraries.
32    OBSD_OLD_GAS:
33       older flavor of gas which needs help for PIC.
34    OBSD_HAS_DECLARE_FUNCTION_NAME, OBSD_HAS_DECLARE_FUNCTION_SIZE,
35    OBSD_HAS_DECLARE_OBJECT:
36       PIC support, FUNCTION_NAME/FUNCTION_SIZE are independent, whereas
37       the corresponding logic for OBJECTS is necessarily coupled.
38 
39    There are also a few `default' defines such as ASM_WEAKEN_LABEL,
40    intended as common ground for arch that don't provide
41    anything suitable.  */
42 
43 /* OPENBSD_NATIVE is defined only when gcc is configured as part of
44    the OpenBSD source tree, specifically through Makefile.bsd-wrapper.
45 
46    In such a case the include path can be trimmed as there is no
47    distinction between system includes and gcc includes.  */
48 
49 /* This configuration method, namely Makefile.bsd-wrapper and
50    OPENBSD_NATIVE is NOT recommended for building cross-compilers.  */
51 
52 #ifdef OPENBSD_NATIVE
53 
54 /* The compiler is configured with ONLY the gcc/g++ standard headers.  */
55 #undef INCLUDE_DEFAULTS
56 #define INCLUDE_DEFAULTS			\
57   {						\
58     { GPLUSPLUS_INCLUDE_DIR, "G++", 1, 1 },	\
59     { GPLUSPLUS_TOOL_INCLUDE_DIR, "G++", 1, 1 }, \
60     { GPLUSPLUS_BACKWARD_INCLUDE_DIR, "G++", 1, 1 }, \
61     { NATIVE_SYSTEM_HEADER_DIR, NATIVE_SYSTEM_HEADER_COMPONENT, 0, 0 }, \
62     { 0, 0, 0, 0 }				\
63   }
64 
65 /* Under OpenBSD, the normal location of the various *crt*.o files is the
66    /usr/lib directory.  */
67 #undef STANDARD_STARTFILE_PREFIX
68 #define STANDARD_STARTFILE_PREFIX	"/usr/local/lib/"
69 
70 #endif
71 
72 
73 /* Controlling the compilation driver.  */
74 /* TARGET_OS_CPP_BUILTINS() common to all OpenBSD targets.  */
75 #define OPENBSD_OS_CPP_BUILTINS()		\
76   do						\
77     {						\
78       builtin_define ("__OpenBSD__");		\
79       builtin_define ("__unix__");		\
80       builtin_define ("__ANSI_COMPAT");		\
81       builtin_assert ("system=unix");		\
82       builtin_assert ("system=bsd");		\
83       builtin_assert ("system=OpenBSD");	\
84     }						\
85   while (0)
86 
87 /* TARGET_OS_CPP_BUILTINS() common to all OpenBSD ELF targets.  */
88 #define OPENBSD_OS_CPP_BUILTINS_ELF()		\
89   do						\
90     {						\
91       OPENBSD_OS_CPP_BUILTINS();		\
92       builtin_define ("__ELF__");		\
93     }						\
94 while (0)
95 
96 /* TARGET_OS_CPP_BUILTINS() common to all LP64 OpenBSD targets.  */
97 #define OPENBSD_OS_CPP_BUILTINS_LP64()		\
98   do						\
99     {						\
100       builtin_define ("_LP64");			\
101       builtin_define ("__LP64__");		\
102     }						\
103   while (0)
104 
105 /* CPP_SPEC appropriate for OpenBSD. We deal with -posix and -pthread.
106    XXX the way threads are handled currently is not very satisfying,
107    since all code must be compiled with -pthread to work.
108    This two-stage defines makes it easy to pick that for targets that
109    have subspecs.  */
110 #ifdef CPP_CPU_SPEC
111 #define OBSD_CPP_SPEC "%(cpp_cpu) %{posix:-D_POSIX_SOURCE} %{pthread:-D_POSIX_THREADS}"
112 #else
113 #define OBSD_CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_POSIX_THREADS}"
114 #endif
115 
116 #undef LIB_SPEC
117 #define LIB_SPEC OBSD_LIB_SPEC
118 
119 #ifndef OBSD_HAS_CORRECT_SPECS
120 
121 #undef CPP_SPEC
122 #define CPP_SPEC OBSD_CPP_SPEC
123 
124 #ifdef OBSD_OLD_GAS
125 /* ASM_SPEC appropriate for OpenBSD.  For some architectures, OpenBSD
126    still uses a special flavor of gas that needs to be told when generating
127    pic code.  */
128 #undef ASM_SPEC
129 #define ASM_SPEC "%{" FPIE1_OR_FPIC1_SPEC ":-k} %{" FPIE2_OR_FPIC2_SPEC ":-k -K}"
130 #endif
131 
132 /* Since we use gas, stdin -> - is a good idea.  */
133 #define AS_NEEDS_DASH_FOR_PIPED_INPUT
134 
135 #undef LIB_SPEC
136 #define LIB_SPEC OBSD_LIB_SPEC
137 
138 #if defined(HAVE_LD_EH_FRAME_HDR)
139 #define LINK_EH_SPEC "%{!static|static-pie:--eh-frame-hdr} "
140 #endif
141 
142 #undef LIB_SPEC
143 #define LIB_SPEC OBSD_LIB_SPEC
144 #endif
145 
146 #define TARGET_POSIX_IO
147 
148 /* All new versions of OpenBSD have C99 functions.  We redefine this hook
149    so the version from elfos.h header won't be used.  */
150 #undef TARGET_LIBC_HAS_FUNCTION
151 #define TARGET_LIBC_HAS_FUNCTION default_libc_has_function
152 
153 
154 /* Runtime target specification.  */
155 
156 /* Miscellaneous parameters.  */
157 
158 /* Controlling debugging info: dbx options.  */
159 
160 /* Don't use the `xsTAG;' construct in DBX output; OpenBSD systems that
161    use DBX don't support it.  */
162 #define DBX_NO_XREFS
163 
164 
165 /* - we use . - _func instead of a local label,
166    - we put extra spaces in expressions such as
167      .type _func , @function
168      This is more readable for a human being and confuses c++filt less.  */
169 
170 /* Assembler format: output and generation of labels.  */
171 
172 /* Define the strings used for the .type and .size directives.
173    These strings generally do not vary from one system running OpenBSD
174    to another, but if a given system needs to use different pseudo-op
175    names for these, they may be overridden in the arch specific file.  */
176 
177 /* OpenBSD assembler is hacked to have .type & .size support even in a.out
178    format object files.  Functions size are supported but not activated
179    yet (look for GRACE_PERIOD_EXPIRED in gas/config/obj-aout.c).
180    SET_ASM_OP is needed for attribute alias to work.  */
181 
182 #undef TYPE_ASM_OP
183 #undef SIZE_ASM_OP
184 #undef SET_ASM_OP
185 #undef GLOBAL_ASM_OP
186 
187 #define TYPE_ASM_OP	"\t.type\t"
188 #define SIZE_ASM_OP	"\t.size\t"
189 #define SET_ASM_OP	"\t.set\t"
190 #define GLOBAL_ASM_OP	"\t.globl\t"
191 
192 /* The following macro defines the format used to output the second
193    operand of the .type assembler directive.  */
194 #undef TYPE_OPERAND_FMT
195 #define TYPE_OPERAND_FMT	"@%s"
196 
197 /* Provision if extra assembler code is needed to declare a function's result
198    (taken from svr4, not needed yet actually).  */
199 #ifndef ASM_DECLARE_RESULT
200 #define ASM_DECLARE_RESULT(FILE, RESULT)
201 #endif
202 
203 /* These macros generate the special .type and .size directives which
204    are used to set the corresponding fields of the linker symbol table
205    entries under OpenBSD.  These macros also have to output the starting
206    labels for the relevant functions/objects.  */
207 
208 #ifndef OBSD_HAS_DECLARE_FUNCTION_NAME
209 /* Extra assembler code needed to declare a function properly.
210    Some assemblers may also need to also have something extra said
211    about the function's return value.  We allow for that here.  */
212 #undef ASM_DECLARE_FUNCTION_NAME
213 #define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL)			\
214   do {									\
215     ASM_OUTPUT_TYPE_DIRECTIVE (FILE, NAME, "function");			\
216     ASM_DECLARE_RESULT (FILE, DECL_RESULT (DECL));			\
217     ASM_OUTPUT_FUNCTION_LABEL (FILE, NAME, DECL);			\
218   } while (0)
219 #endif
220 
221 #ifndef OBSD_HAS_DECLARE_FUNCTION_SIZE
222 /* Declare the size of a function.  */
223 #undef ASM_DECLARE_FUNCTION_SIZE
224 #define ASM_DECLARE_FUNCTION_SIZE(FILE, FNAME, DECL)		\
225   do {								\
226     if (!flag_inhibit_size_directive)				\
227       ASM_OUTPUT_MEASURED_SIZE (FILE, FNAME);			\
228   } while (0)
229 #endif
230 
231 #ifndef OBSD_HAS_DECLARE_OBJECT
232 /* Extra assembler code needed to declare an object properly.  */
233 #undef ASM_DECLARE_OBJECT_NAME
234 #define ASM_DECLARE_OBJECT_NAME(FILE, NAME, DECL)		\
235   do {								\
236       HOST_WIDE_INT size;					\
237       ASM_OUTPUT_TYPE_DIRECTIVE (FILE, NAME, "object");		\
238       size_directive_output = 0;				\
239       if (!flag_inhibit_size_directive				\
240 	  && (DECL) && DECL_SIZE (DECL))			\
241 	{							\
242 	  size_directive_output = 1;				\
243 	  size = int_size_in_bytes (TREE_TYPE (DECL));		\
244 	  ASM_OUTPUT_SIZE_DIRECTIVE (FILE, NAME, size);		\
245 	}							\
246       ASM_OUTPUT_LABEL (FILE, NAME);				\
247   } while (0)
248 
249 /* Output the size directive for a decl in rest_of_decl_compilation
250    in the case where we did not do so before the initializer.
251    Once we find the error_mark_node, we know that the value of
252    size_directive_output was set by ASM_DECLARE_OBJECT_NAME
253    when it was run for the same decl.  */
254 #undef ASM_FINISH_DECLARE_OBJECT
255 #define ASM_FINISH_DECLARE_OBJECT(FILE, DECL, TOP_LEVEL, AT_END)	 \
256 do {									 \
257      const char *name = XSTR (XEXP (DECL_RTL (DECL), 0), 0);		 \
258      HOST_WIDE_INT size;						 \
259      if (!flag_inhibit_size_directive && DECL_SIZE (DECL)		 \
260          && ! AT_END && TOP_LEVEL					 \
261 	 && DECL_INITIAL (DECL) == error_mark_node			 \
262 	 && !size_directive_output)					 \
263        {								 \
264 	 size_directive_output = 1;					 \
265 	 size = int_size_in_bytes (TREE_TYPE (DECL));			 \
266 	 ASM_OUTPUT_SIZE_DIRECTIVE (FILE, name, size);			 \
267        }								 \
268    } while (0)
269 #endif
270 
271 
272 /* Those are `generic' ways to weaken/globalize a label. We shouldn't need
273    to override a processor specific definition. Hence, #ifndef ASM_*
274    In case overriding turns out to be needed, one can always #undef ASM_*
275    before including this file.  */
276 
277 /* Tell the assembler that a symbol is weak.  */
278 /* Note: netbsd arm32 assembler needs a .globl here. An override may
279    be needed when/if we go for arm32 support.  */
280 #ifndef ASM_WEAKEN_LABEL
281 #define ASM_WEAKEN_LABEL(FILE,NAME) \
282   do { fputs ("\t.weak\t", FILE); assemble_name (FILE, NAME); \
283        fputc ('\n', FILE); } while (0)
284 #endif
285 
286 /* Storage layout.  */
287 
288 
289 #define HAVE_ENABLE_EXECUTE_STACK
290