support weak attribute on variables

master
Joe Soroka 2011-02-01 00:37:53 -08:00
parent 6839382480
commit 4d5105c8f1
4 changed files with 29 additions and 4 deletions

View File

@ -429,7 +429,7 @@ ST_FUNC void put_extern_sym2(Sym *sym, Section *section,
if (sym->type.t & VT_STATIC)
sym_bind = STB_LOCAL;
else {
if (sym_type == STT_FUNC && sym->type.ref && FUNC_WEAK(sym->type.ref->r))
if (sym->type.t & VT_WEAK)
sym_bind = STB_WEAK;
else
sym_bind = STB_GLOBAL;

6
tcc.h
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@ -293,7 +293,6 @@ typedef struct AttributeDef {
#define FUNC_ARGS(r) (((AttributeDef*)&(r))->func_args)
#define FUNC_ALIGN(r) (((AttributeDef*)&(r))->aligned)
#define FUNC_PACKED(r) (((AttributeDef*)&(r))->packed)
#define FUNC_WEAK(r) (((AttributeDef*)&(r))->weak)
#define ATTR_MODE(r) (((AttributeDef*)&(r))->mode)
#define INT_ATTR(ad) (*(int*)(ad))
@ -629,11 +628,12 @@ struct TCCState {
#define VT_INLINE 0x00000400 /* inline definition */
#define VT_IMPORT 0x00004000 /* win32: extern data imported from dll */
#define VT_EXPORT 0x00008000 /* win32: data exported from dll */
#define VT_WEAK 0x00010000 /* win32: data exported from dll */
#define VT_STRUCT_SHIFT 16 /* shift for bitfield shift values */
#define VT_STRUCT_SHIFT 17 /* shift for bitfield shift values */
/* type mask (except storage) */
#define VT_STORAGE (VT_EXTERN | VT_STATIC | VT_TYPEDEF | VT_INLINE | VT_IMPORT | VT_EXPORT)
#define VT_STORAGE (VT_EXTERN | VT_STATIC | VT_TYPEDEF | VT_INLINE | VT_IMPORT | VT_EXPORT | VT_WEAK)
#define VT_TYPE (~(VT_STORAGE))
/* token values */

View File

@ -2922,6 +2922,9 @@ static int parse_btype(CType *type, AttributeDef *ad)
case TOK_ATTRIBUTE1:
case TOK_ATTRIBUTE2:
parse_attribute(ad);
if (ad->weak) {
t |= VT_WEAK;
}
if (ad->mode) {
u = ad->mode -1;
t = (t & ~VT_BTYPE) | u;
@ -3189,6 +3192,10 @@ static void type_decl(CType *type, AttributeDef *ad, int *v, int td)
post_type(type, ad);
if (tok == TOK_ATTRIBUTE1 || tok == TOK_ATTRIBUTE2)
parse_attribute(ad);
if (ad->weak)
type->t |= VT_WEAK;
if (!type1.t)
return;
/* append type at the end of type1 */

View File

@ -82,6 +82,7 @@ void local_label_test(void);
void statement_expr_test(void);
void asm_test(void);
void builtin_test(void);
void weak_test(void);
int fib(int n);
void num(int n);
@ -537,6 +538,7 @@ int main(int argc, char **argv)
local_label_test();
asm_test();
builtin_test();
weak_test();
return 0;
}
@ -2227,6 +2229,22 @@ void builtin_test(void)
}
extern int __attribute__((weak)) weak_f1(void);
extern int __attribute__((weak)) weak_f2(void);
extern int __attribute__((weak)) weak_v1;
extern int __attribute__((weak)) weak_v2;
void __attribute__((weak)) weak_test(void)
{
printf("weak_f1=%d\n", weak_f1 ? weak_f1() : 123);
printf("weak_f2=%d\n", weak_f2 ? weak_f2() : 123);
printf("weak_v1=%d\n",&weak_v1 ? weak_v1 : 123);
printf("weak_v2=%d\n",&weak_v2 ? weak_v2 : 123);
}
int __attribute__((weak)) weak_f2() { return 222; }
int __attribute__((weak)) weak_v2 = 222;
void const_func(const int a)
{
}