1/*
2 If G_HAS_CONSTRUCTORS is true then the compiler support *both* constructors and
3 destructors, in a sane way, including e.g. on library unload. If not you're on
4 your own.
5
6 Some compilers need #pragma to handle this, which does not work with macros,
7 so the way you need to use this is (for constructors):
8
9 #ifdef G_DEFINE_CONSTRUCTOR_NEEDS_PRAGMA
10 #pragma G_DEFINE_CONSTRUCTOR_PRAGMA_ARGS(my_constructor)
11 #endif
12 G_DEFINE_CONSTRUCTOR(my_constructor)
13 static void my_constructor(void) {
14 ...
15 }
16
17*/
18
19#ifndef __GTK_DOC_IGNORE__
20
21#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
22
23#define G_HAS_CONSTRUCTORS 1
24
25#define G_DEFINE_CONSTRUCTOR(_func) static void __attribute__((constructor)) _func (void);
26#define G_DEFINE_DESTRUCTOR(_func) static void __attribute__((destructor)) _func (void);
27
28#elif defined (_MSC_VER) && (_MSC_VER >= 1500)
29/* Visual studio 2008 and later has _Pragma */
30
31#define G_HAS_CONSTRUCTORS 1
32
33/* We do some weird things to avoid the constructors being optimized
34 * away on VS2015 if WholeProgramOptimization is enabled. First we
35 * make a reference to the array from the wrapper to make sure its
36 * references. Then we use a pragma to make sure the wrapper function
37 * symbol is always included at the link stage. Also, the symbols
38 * need to be extern (but not dllexport), even though they are not
39 * really used from another object file.
40 */
41
42/* We need to account for differences between the mangling of symbols
43 * for Win32 (x86) and x64 programs, as symbols on Win32 are prefixed
44 * with an underscore but symbols on x64 are not.
45 */
46#ifdef _WIN64
47#define G_MSVC_SYMBOL_PREFIX ""
48#else
49#define G_MSVC_SYMBOL_PREFIX "_"
50#endif
51
52#define G_DEFINE_CONSTRUCTOR(_func) G_MSVC_CTOR (_func, G_MSVC_SYMBOL_PREFIX)
53#define G_DEFINE_DESTRUCTOR(_func) G_MSVC_DTOR (_func, G_MSVC_SYMBOL_PREFIX)
54
55#define G_MSVC_CTOR(_func,_sym_prefix) \
56 static void _func(void); \
57 extern int (* _array ## _func)(void); \
58 int _func ## _wrapper(void) { _func(); g_slist_find (NULL, _array ## _func); return 0; } \
59 __pragma(comment(linker,"/include:" _sym_prefix # _func "_wrapper")) \
60 __pragma(section(".CRT$XCU",read)) \
61 __declspec(allocate(".CRT$XCU")) int (* _array ## _func)(void) = _func ## _wrapper;
62
63#define G_MSVC_DTOR(_func,_sym_prefix) \
64 static void _func(void); \
65 extern int (* _array ## _func)(void); \
66 int _func ## _constructor(void) { atexit (_func); g_slist_find (NULL, _array ## _func); return 0; } \
67 __pragma(comment(linker,"/include:" _sym_prefix # _func "_constructor")) \
68 __pragma(section(".CRT$XCU",read)) \
69 __declspec(allocate(".CRT$XCU")) int (* _array ## _func)(void) = _func ## _constructor;
70
71#elif defined (_MSC_VER)
72
73#define G_HAS_CONSTRUCTORS 1
74
75/* Pre Visual studio 2008 must use #pragma section */
76#define G_DEFINE_CONSTRUCTOR_NEEDS_PRAGMA 1
77#define G_DEFINE_DESTRUCTOR_NEEDS_PRAGMA 1
78
79#define G_DEFINE_CONSTRUCTOR_PRAGMA_ARGS(_func) \
80 section(".CRT$XCU",read)
81#define G_DEFINE_CONSTRUCTOR(_func) \
82 static void _func(void); \
83 static int _func ## _wrapper(void) { _func(); return 0; } \
84 __declspec(allocate(".CRT$XCU")) static int (*p)(void) = _func ## _wrapper;
85
86#define G_DEFINE_DESTRUCTOR_PRAGMA_ARGS(_func) \
87 section(".CRT$XCU",read)
88#define G_DEFINE_DESTRUCTOR(_func) \
89 static void _func(void); \
90 static int _func ## _constructor(void) { atexit (_func); return 0; } \
91 __declspec(allocate(".CRT$XCU")) static int (* _array ## _func)(void) = _func ## _constructor;
92
93#elif defined(__SUNPRO_C)
94
95/* This is not tested, but i believe it should work, based on:
96 * http://opensource.apple.com/source/OpenSSL098/OpenSSL098-35/src/fips/fips_premain.c
97 */
98
99#define G_HAS_CONSTRUCTORS 1
100
101#define G_DEFINE_CONSTRUCTOR_NEEDS_PRAGMA 1
102#define G_DEFINE_DESTRUCTOR_NEEDS_PRAGMA 1
103
104#define G_DEFINE_CONSTRUCTOR_PRAGMA_ARGS(_func) \
105 init(_func)
106#define G_DEFINE_CONSTRUCTOR(_func) \
107 static void _func(void);
108
109#define G_DEFINE_DESTRUCTOR_PRAGMA_ARGS(_func) \
110 fini(_func)
111#define G_DEFINE_DESTRUCTOR(_func) \
112 static void _func(void);
113
114#else
115
116/* constructors not supported for this compiler */
117
118#endif
119
120#endif /* __GTK_DOC_IGNORE__ */
121

source code of gtk/gdk/gdkconstructor.h