1 /* crtbegin object for windows32 targets.
2 Copyright (C) 2007-2014 Free Software Foundation, Inc.
4 Contributed by Danny Smith <dannysmith@users.sourceforge.net>
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 Under Section 7 of GPL version 3, you are granted additional
19 permissions described in the GCC Runtime Library Exception, version
20 3.1, as published by the Free Software Foundation.
22 You should have received a copy of the GNU General Public License and
23 a copy of the GCC Runtime Library Exception along with this program;
24 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
25 <http://www.gnu.org/licenses/>. */
27 /* Target machine header files require this define. */
30 #include "auto-host.h"
33 #include "coretypes.h"
35 #include "libgcc_tm.h"
36 #include "unwind-dw2-fde.h"
38 #define WIN32_LEAN_AND_MEAN
42 #define LIBGCC_SONAME "libgcc_s.dll"
46 #define LIBGCJ_SONAME "libgcj_s.dll"
49 #if DWARF2_UNWIND_INFO
50 /* Make the declarations weak. This is critical for
51 _Jv_RegisterClasses because it lives in libgcj.a */
52 extern void __register_frame_info (__attribute__((unused
)) const void *,
53 __attribute__((unused
)) struct object
*)
54 TARGET_ATTRIBUTE_WEAK
;
55 extern void *__deregister_frame_info (__attribute__((unused
)) const void *)
56 TARGET_ATTRIBUTE_WEAK
;
58 /* Work around for current cygwin32 build problems (Bug gas/16858).
59 Compile weak default functions only for 64-bit systems,
60 when absolutely necessary. */
62 TARGET_ATTRIBUTE_WEAK
void
63 __register_frame_info (__attribute__((unused
)) const void *p
,
64 __attribute__((unused
)) struct object
*o
)
68 TARGET_ATTRIBUTE_WEAK
void *
69 __deregister_frame_info (__attribute__((unused
)) const void *p
)
74 #endif /* DWARF2_UNWIND_INFO */
76 #if TARGET_USE_JCR_SECTION
77 extern void _Jv_RegisterClasses (__attribute__((unused
)) const void *)
78 TARGET_ATTRIBUTE_WEAK
;
81 TARGET_ATTRIBUTE_WEAK
void
82 _Jv_RegisterClasses (__attribute__((unused
)) const void *p
)
86 #endif /* TARGET_USE_JCR_SECTION */
88 #if defined(HAVE_LD_RO_RW_SECTION_MIXING)
89 # define EH_FRAME_SECTION_CONST const
91 # define EH_FRAME_SECTION_CONST
94 /* Stick a label at the beginning of the frame unwind info so we can
95 register/deregister it with the exception handling library code. */
96 #if DWARF2_UNWIND_INFO
97 static EH_FRAME_SECTION_CONST
char __EH_FRAME_BEGIN__
[]
98 __attribute__((used
, section(EH_FRAME_SECTION_NAME
), aligned(4)))
101 static struct object obj
;
103 /* Handle of libgcc's DLL reference. */
105 static void * (*deregister_frame_fn
) (const void *) == NULL
;
108 #if TARGET_USE_JCR_SECTION
109 static void *__JCR_LIST__
[]
110 __attribute__ ((used
, section(JCR_SECTION_NAME
), aligned(4)))
114 /* Pull in references from libgcc.a(unwind-dw2-fde.o) in the
115 startfile. These are referenced by a ctor and dtor in crtend.o. */
116 extern void __gcc_register_frame (void);
117 extern void __gcc_deregister_frame (void);
120 __gcc_register_frame (void)
122 #if DWARF2_UNWIND_INFO
123 /* Weak undefined symbols won't be pulled in from dlls; hence
124 we first test if the dll is already loaded and, if so,
125 get the symbol's address at run-time. If the dll is not loaded,
126 fallback to weak linkage to static archive. */
128 void (*register_frame_fn
) (const void *, struct object
*);
129 HANDLE h
= GetModuleHandle (LIBGCC_SONAME
);
133 /* Increasing the load-count of LIBGCC_SONAME DLL. */
134 hmod_libgcc
= LoadLibrary (LIBGCC_SONAME
);
135 register_frame_fn
= (void (*) (const void *, struct object
*))
136 GetProcAddress (h
, "__register_frame_info");
137 deregister_frame_fn
= (void* (*) (const void *))
138 GetProcAddress (h
, "__deregister_frame_info");
142 register_frame_fn
= __register_frame_info
;
143 deregister_frame_fn
= __deregister_frame_info
;
145 if (register_frame_fn
)
146 register_frame_fn (__EH_FRAME_BEGIN__
, &obj
);
149 #if TARGET_USE_JCR_SECTION
152 void (*register_class_fn
) (const void *);
153 HANDLE h
= GetModuleHandle (LIBGCJ_SONAME
);
155 register_class_fn
= (void (*) (const void *))
156 GetProcAddress (h
, "_Jv_RegisterClasses");
158 register_class_fn
= _Jv_RegisterClasses
;
160 if (register_class_fn
)
161 register_class_fn (__JCR_LIST__
);
167 __gcc_deregister_frame (void)
169 #if DWARF2_UNWIND_INFO
170 if (deregister_frame_fn
)
171 deregister_frame_fn (__EH_FRAME_BEGIN__
);
173 FreeLibrary (hmod_libgcc
);