diff options
| -rw-r--r-- | tcc.h | 12 | ||||
| -rw-r--r-- | tccgen.c | 60 | ||||
| -rw-r--r-- | tcctok.h | 2 |
3 files changed, 69 insertions, 5 deletions
@@ -375,7 +375,8 @@ struct Attribute { func_proto : 1, mode : 4, weak : 1, - fill : 10; // 10 bits left to fit well in union below + visibility : 2, + fill : 8; // 8 bits left to fit well in union below }; /* GNUC attribute definition */ @@ -787,11 +788,18 @@ struct TCCState { #define VT_EXPORT 0x00008000 /* win32: data exported from dll */ #define VT_WEAK 0x00010000 /* weak symbol */ #define VT_TLS 0x00040000 /* thread-local storage */ +#define VT_VIS_SHIFT 19 /* shift for symbol visibility, overlapping + bitfield values, because bitfields never + have linkage and hence never have + visibility. */ +#define VT_VIS_SIZE 2 /* We have four visibilities. */ +#define VT_VIS_MASK (((1 << VT_VIS_SIZE)-1) << VT_VIS_SHIFT) #define VT_STRUCT_SHIFT 19 /* shift for bitfield shift values (max: 32 - 2*6) */ + /* type mask (except storage) */ -#define VT_STORAGE (VT_EXTERN | VT_STATIC | VT_TYPEDEF | VT_INLINE | VT_IMPORT | VT_EXPORT | VT_WEAK) +#define VT_STORAGE (VT_EXTERN | VT_STATIC | VT_TYPEDEF | VT_INLINE | VT_IMPORT | VT_EXPORT | VT_WEAK | VT_VIS_MASK) #define VT_TYPE (~(VT_STORAGE)) /* token values */ @@ -300,6 +300,29 @@ static void weaken_symbol(Sym *sym) } } +static void apply_visibility(Sym *sym, CType *type) +{ + int vis = sym->type.t & VT_VIS_MASK; + int vis2 = type->t & VT_VIS_MASK; + if (vis == (STV_DEFAULT << VT_VIS_SHIFT)) + vis = vis2; + else if (vis2 == (STV_DEFAULT << VT_VIS_SHIFT)) + ; + else + vis = (vis < vis2) ? vis : vis2; + sym->type.t &= ~VT_VIS_MASK; + sym->type.t |= vis; + + if (sym->c > 0) { + int esym_type; + ElfW(Sym) *esym; + + esym = &((ElfW(Sym) *)symtab_section->data)[sym->c]; + vis >>= VT_VIS_SHIFT; + esym->st_other = (esym->st_other & ~ELFW(ST_VISIBILITY)(-1)) | vis; + } +} + /* ------------------------------------------------------------------------- */ ST_FUNC void swap(int *p, int *q) @@ -436,6 +459,13 @@ static Sym *external_sym(int v, CType *type, int r, char *asm_label) tcc_error("incompatible types for redefinition of '%s'", get_tok_str(v, NULL)); } + /* Merge some storage attributes. */ + if (type->t & VT_WEAK) + weaken_symbol(s); + + if (type->t & VT_VIS_MASK) + apply_visibility(s, type); + return s; } @@ -2662,6 +2692,24 @@ static void parse_attribute(AttributeDef *ad) next(); skip(')'); break; + case TOK_VISIBILITY1: + case TOK_VISIBILITY2: + skip('('); + if (tok != TOK_STR) + expect("visibility(\"default|hidden|internal|protected\")"); + if (!strcmp (tokc.cstr->data, "default")) + ad->a.visibility = STV_DEFAULT; + else if (!strcmp (tokc.cstr->data, "hidden")) + ad->a.visibility = STV_HIDDEN; + else if (!strcmp (tokc.cstr->data, "internal")) + ad->a.visibility = STV_INTERNAL; + else if (!strcmp (tokc.cstr->data, "protected")) + ad->a.visibility = STV_PROTECTED; + else + expect("visibility(\"default|hidden|internal|protected\")"); + next(); + skip(')'); + break; case TOK_ALIGNED1: case TOK_ALIGNED2: if (tok == '(') { @@ -5656,6 +5704,7 @@ static void decl_initializer_alloc(CType *type, AttributeDef *ad, int r, /* patch symbol weakness */ if (type->t & VT_WEAK) weaken_symbol(sym); + apply_visibility(sym, type); #ifdef CONFIG_TCC_BCHECK /* handles bounds now because the symbol must be defined before for the relocation */ @@ -5801,6 +5850,7 @@ static void gen_function(Sym *sym) /* patch symbol weakness (this definition overrules any prototype) */ if (sym->type.t & VT_WEAK) weaken_symbol(sym); + apply_visibility(sym, &sym->type); if (tcc_state->do_debug) { put_stabn(N_FUN, 0, 0, ind - func_ind); } @@ -5934,6 +5984,8 @@ static int decl0(int l, int is_for_loop_init) if (ad.a.func_export) type.t |= VT_EXPORT; #endif + type.t |= ad.a.visibility << VT_VIS_SHIFT; + if (tok == '{') { if (l == VT_LOCAL) tcc_error("cannot use local functions"); @@ -5973,6 +6025,11 @@ static int decl0(int l, int is_for_loop_init) if (sym->type.t & VT_STATIC) type.t = (type.t & ~VT_EXTERN) | VT_STATIC; + /* If the definition has no visibility use the + one from prototype. */ + if (! (type.t & VT_VIS_MASK)) + type.t |= sym->type.t & VT_VIS_MASK; + if (!is_compatible_types(&sym->type, &type)) { func_error1: tcc_error("incompatible types for redefinition of '%s'", @@ -6063,9 +6120,6 @@ static int decl0(int l, int is_for_loop_init) extern */ sym = external_sym(v, &type, r, asm_label); - if (type.t & VT_WEAK) - weaken_symbol(sym); - if (ad.alias_target) { Section tsec; Elf32_Sym *esym; @@ -121,6 +121,8 @@ DEF(TOK_DLLIMPORT, "dllimport") DEF(TOK_NORETURN1, "noreturn") DEF(TOK_NORETURN2, "__noreturn__") + DEF(TOK_VISIBILITY1, "visibility") + DEF(TOK_VISIBILITY2, "__visibility__") DEF(TOK_builtin_types_compatible_p, "__builtin_types_compatible_p") DEF(TOK_builtin_constant_p, "__builtin_constant_p") DEF(TOK_builtin_frame_address, "__builtin_frame_address") |