#include <stdio.h> #include <stdlib.h> int main(void) { printf("識別子使用可能文字\n"); int ABCDEFGHIJKLMNOPQRSTUVWXYZ = 12; /* 英大文字 */ int abcdefghijklmnopqrstuvwxyz = 34; /* 英小文字 */ int _ = 56; /* 下線文字 */ int a0123456789 = 78; /* 数字(先頭以外) */ int あいうえお = 90; /* マルチバイト文字(実装による) */ printf("ABCDEFGHIJKLMNOPQRSTUVWXYZ = %d\n", ABCDEFGHIJKLMNOPQRSTUVWXYZ); printf("abcdefghijklmnopqrstuvwxyz = %d\n", abcdefghijklmnopqrstuvwxyz); printf("_ = %d\n", _); printf("a0123456789 = %d\n", a0123456789); printf("あいうえお = %d\n", あいうえお); return EXIT_SUCCESS; }

#include <ansidecl.h> /* ---------- gcc-12.2.0/gcc/c-family/c-common.h 63行目～278行目 ---------- */ enum rid { /* Modifiers: */ /* C, in empirical order of frequency. */ RID_STATIC = 0, RID_UNSIGNED, RID_LONG, RID_CONST, RID_EXTERN, ︙ RID_FIRST_PATTR = RID_GETTER, RID_LAST_PATTR = RID_NULL_RESETTABLE }; /* ---------- gcc-12.2.0/gcc/c-family/c-common.h 63行目～278行目 ---------- */ /* ---------- gcc-12.2.0/gcc/c-family/c-common.h 401行目～408行目 ---------- */ /* An entry in the reserved keyword table. */ struct c_common_resword { const char *const word; ENUM_BITFIELD(rid) const rid : 16; const unsigned int disable : 16; }; /* ---------- gcc-12.2.0/gcc/c-family/c-common.h 401行目～408行目 ---------- */ /* ---------- gcc-12.2.0/gcc/c-family/c-common.h 442行目～278行目 ---------- */ #define D_CONLY 0x0001 /* C only (not in C++). */ #define D_CXXONLY 0x0002 /* C++ only (not in C). */ ︙ #define D_CXX_MODULES_FLAGS (D_CXXONLY | D_CXX_MODULES) #define D_CXX_COROUTINES_FLAGS (D_CXXONLY | D_CXX_COROUTINES) /* ---------- gcc-12.2.0/gcc/c-family/c-common.h 442行目～278行目 ---------- */ /* ---------- gcc-12.2.0/gcc/c-family/c-common.cc 343行目～603行目 --------- */ const struct c_common_resword c_common_reswords[] = { { "_Alignas", RID_ALIGNAS, D_CONLY }, { "_Alignof", RID_ALIGNOF, D_CONLY }, ︙ { "nonnull", RID_NONNULL, D_OBJC }, { "null_resettable", RID_NULL_RESETTABLE, D_OBJC }, }; /* ---------- gcc-12.2.0/gcc/c-family/c-common.cc 343行目～603行目 --------- */

#include <stdio.h> #include <stdlib.h> #include "sample.h" int main(void) { for (int i=0; i<238; i++) { if (c_common_reswords[i].disable & (D_CXXONLY | D_CXX11 | D_OBJC | D_CXXWARN | D_CXX_CONCEPTS | D_TRANSMEM | D_CXX_CHAR8_T | D_CXX20 | D_CXX_COROUTINES | D_CXX_MODULES | D_CXX_CONCEPTS_FLAGS | D_CXX_CHAR8_T_FLAGS | D_CXX_MODULES_FLAGS | D_CXX_COROUTINES_FLAGS)) { printf("int %s = %d; ", c_common_reswords[i].word, c_common_reswords[i].rid); printf("printf(\"%s = %%d\\n\", %s);\n", c_common_reswords[i].word, c_common_reswords[i].word); } } return EXIT_SUCCESS; }

#include <stdio.h> #include <stdlib.h> int main(void) { int __bases = 137; printf("__bases = %d\n", __bases); int __builtin_addressof = 136; printf("__builtin_addressof = %d\n", __builtin_addressof); int __builtin_bit_cast = 149; printf("__builtin_bit_cast = %d\n", __builtin_bit_cast); int __builtin_launder = 138; printf("__builtin_launder = %d\n", __builtin_launder); int __constinit = 179; printf("__constinit = %d\n", __constinit); int __decltype = 175; printf("__decltype = %d\n", __decltype); int __direct_bases = 139; printf("__direct_bases = %d\n", __direct_bases); int __has_nothrow_assign = 140; printf("__has_nothrow_assign = %d\n", __has_nothrow_assign); int __has_nothrow_constructor = 141; printf("__has_nothrow_constructor = %d\n", __has_nothrow_constructor); int __has_nothrow_copy = 142; printf("__has_nothrow_copy = %d\n", __has_nothrow_copy); int __has_trivial_assign = 143; printf("__has_trivial_assign = %d\n", __has_trivial_assign); int __has_trivial_constructor = 144; printf("__has_trivial_constructor = %d\n", __has_trivial_constructor); int __has_trivial_copy = 145; printf("__has_trivial_copy = %d\n", __has_trivial_copy); int __has_trivial_destructor = 146; printf("__has_trivial_destructor = %d\n", __has_trivial_destructor); int __has_unique_object_representations = 147; printf("__has_unique_object_representations = %d\n", __has_unique_object_representations); int __has_virtual_destructor = 148; printf("__has_virtual_destructor = %d\n", __has_virtual_destructor); int __is_abstract = 150; printf("__is_abstract = %d\n", __is_abstract); int __is_aggregate = 151; printf("__is_aggregate = %d\n", __is_aggregate); int __is_base_of = 152; printf("__is_base_of = %d\n", __is_base_of); int __is_class = 153; printf("__is_class = %d\n", __is_class); int __is_empty = 154; printf("__is_empty = %d\n", __is_empty); int __is_enum = 155; printf("__is_enum = %d\n", __is_enum); int __is_final = 156; printf("__is_final = %d\n", __is_final); int __is_layout_compatible = 157; printf("__is_layout_compatible = %d\n", __is_layout_compatible); int __is_literal_type = 158; printf("__is_literal_type = %d\n", __is_literal_type); int __is_pointer_interconvertible_base_of = 159; printf("__is_pointer_interconvertible_base_of = %d\n", __is_pointer_interconvertible_base_of); int __is_pod = 160; printf("__is_pod = %d\n", __is_pod); int __is_polymorphic = 161; printf("__is_polymorphic = %d\n", __is_polymorphic); int __is_same = 162; printf("__is_same = %d\n", __is_same); int __is_same_as = 162; printf("__is_same_as = %d\n", __is_same_as); int __is_standard_layout = 163; printf("__is_standard_layout = %d\n", __is_standard_layout); int __is_trivial = 164; printf("__is_trivial = %d\n", __is_trivial); int __is_trivially_assignable = 165; printf("__is_trivially_assignable = %d\n", __is_trivially_assignable); int __is_trivially_constructible = 166; printf("__is_trivially_constructible = %d\n", __is_trivially_constructible); int __is_trivially_copyable = 167; printf("__is_trivially_copyable = %d\n", __is_trivially_copyable); int __is_union = 168; printf("__is_union = %d\n", __is_union); int __underlying_type = 169; printf("__underlying_type = %d\n", __underlying_type); int alignas = 99; printf("alignas = %d\n", alignas); int alignof = 66; printf("alignof = %d\n", alignof); int bool = 108; printf("bool = %d\n", bool); int catch = 116; printf("catch = %d\n", catch); int char8_t = 181; printf("char8_t = %d\n", char8_t); int char16_t = 130; printf("char16_t = %d\n", char16_t); int char32_t = 131; printf("char32_t = %d\n", char32_t); int class = 110; printf("class = %d\n", class); int consteval = 180; printf("consteval = %d\n", consteval); int constexpr = 174; printf("constexpr = %d\n", constexpr); int constinit = 179; printf("constinit = %d\n", constinit); int const_cast = 132; printf("const_cast = %d\n", const_cast); int decltype = 175; printf("decltype = %d\n", decltype); int delete = 117; printf("delete = %d\n", delete); int dynamic_cast = 133; printf("dynamic_cast = %d\n", dynamic_cast); int explicit = 20; printf("explicit = %d\n", explicit); int export = 21; printf("export = %d\n", export); int false = 118; printf("false = %d\n", false); int friend = 18; printf("friend = %d\n", friend); int mutable = 22; printf("mutable = %d\n", mutable); int namespace = 119; printf("namespace = %d\n", namespace); int new = 120; printf("new = %d\n", new); int noexcept = 176; printf("noexcept = %d\n", noexcept); int nullptr = 177; printf("nullptr = %d\n", nullptr); int operator = 122; printf("operator = %d\n", operator); int private = 112; printf("private = %d\n", private); int protected = 113; printf("protected = %d\n", protected); int public = 111; printf("public = %d\n", public); int reinterpret_cast = 134; printf("reinterpret_cast = %d\n", reinterpret_cast); int static_assert = 178; printf("static_assert = %d\n", static_assert); int static_cast = 135; printf("static_cast = %d\n", static_cast); int template = 114; printf("template = %d\n", template); int this = 123; printf("this = %d\n", this); int thread_local = 16; printf("thread_local = %d\n", thread_local); int throw = 124; printf("throw = %d\n", throw); int true = 125; printf("true = %d\n", true); int try = 126; printf("try = %d\n", try); int typename = 127; printf("typename = %d\n", typename); int typeid = 128; printf("typeid = %d\n", typeid); int using = 129; printf("using = %d\n", using); int virtual = 19; printf("virtual = %d\n", virtual); int wchar_t = 109; printf("wchar_t = %d\n", wchar_t); int __is_assignable = 170; printf("__is_assignable = %d\n", __is_assignable); int __is_constructible = 171; printf("__is_constructible = %d\n", __is_constructible); int __is_nothrow_assignable = 172; printf("__is_nothrow_assignable = %d\n", __is_nothrow_assignable); int __is_nothrow_constructible = 173; printf("__is_nothrow_constructible = %d\n", __is_nothrow_constructible); int synchronized = 192; printf("synchronized = %d\n", synchronized); int atomic_noexcept = 190; printf("atomic_noexcept = %d\n", atomic_noexcept); int atomic_cancel = 191; printf("atomic_cancel = %d\n", atomic_cancel); int atomic_commit = 102; printf("atomic_commit = %d\n", atomic_commit); int concept = 182; printf("concept = %d\n", concept); int requires = 183; printf("requires = %d\n", requires); int module = 184; printf("module = %d\n", module ); int import = 185; printf("import = %d\n", import ); /* int export = 186; printf("export = %d\n", export ); 重複回避のためコメントアウト*/ int co_await = 187; printf("co_await = %d\n", co_await); int co_yield = 188; printf("co_yield = %d\n", co_yield); int co_return = 189; printf("co_return = %d\n", co_return); int compatibility_alias = 196; printf("compatibility_alias = %d\n", compatibility_alias); int defs = 197; printf("defs = %d\n", defs); int encode = 193; printf("encode = %d\n", encode); int end = 194; printf("end = %d\n", end); int implementation = 215; printf("implementation = %d\n", implementation); int interface = 214; printf("interface = %d\n", interface); int protocol = 202; printf("protocol = %d\n", protocol); int selector = 203; printf("selector = %d\n", selector); int finally = 207; printf("finally = %d\n", finally); int optional = 209; printf("optional = %d\n", optional); int required = 210; printf("required = %d\n", required); int property = 211; printf("property = %d\n", property); int package = 201; printf("package = %d\n", package); int synthesize = 212; printf("synthesize = %d\n", synthesize); int dynamic = 213; printf("dynamic = %d\n", dynamic); int bycopy = 26; printf("bycopy = %d\n", bycopy); int byref = 27; printf("byref = %d\n", byref); int in = 23; printf("in = %d\n", in); int inout = 25; printf("inout = %d\n", inout); int oneway = 28; printf("oneway = %d\n", oneway); int out = 24; printf("out = %d\n", out); int assign = 33; printf("assign = %d\n", assign); int atomic = 36; printf("atomic = %d\n", atomic); int copy = 35; printf("copy = %d\n", copy); int getter = 29; printf("getter = %d\n", getter); int nonatomic = 37; printf("nonatomic = %d\n", nonatomic); int readonly = 31; printf("readonly = %d\n", readonly); int readwrite = 32; printf("readwrite = %d\n", readwrite); int retain = 34; printf("retain = %d\n", retain); int setter = 30; printf("setter = %d\n", setter); int null_unspecified = 38; printf("null_unspecified = %d\n", null_unspecified); int nullable = 39; printf("nullable = %d\n", nullable); int nonnull = 40; printf("nonnull = %d\n", nonnull); int null_resettable = 41; printf("null_resettable = %d\n", null_resettable); return EXIT_SUCCESS; }

#include <stdio.h> #include <stdlib.h> #include "sample.h" int main(void) { for (int i=0; i<238; i++) { if (!(c_common_reswords[i].disable & (D_CXXONLY | D_CXX11 | D_OBJC | D_CXXWARN | D_CXX_CONCEPTS | D_TRANSMEM | D_CXX_CHAR8_T | D_CXX20 | D_CXX_COROUTINES | D_CXX_MODULES | D_CXX_CONCEPTS_FLAGS | D_CXX_CHAR8_T_FLAGS | D_CXX_MODULES_FLAGS | D_CXX_COROUTINES_FLAGS))) { printf("%03d %02X %s\n", c_common_reswords[i].rid, c_common_reswords[i].disable, c_common_reswords[i].word); } } return EXIT_SUCCESS; }

#include <stdio.h> #include <stdlib.h> /* マクロ名 */ #define ID_MACRO_NAME1 123 #define ID_MACRO_NAME2 456 /* 構造体タグ名 */ struct id_struct_tag { /* 構造体メンバ名 */ int id_struct_mem; }; /* 共用体タグ名 */ union id_union_tag { /* 共用体メンバ名 */ char id_union_mem1[4]; int id_union_mem2; }; /* 列挙型タグ名 */ enum id_enum_tag { /* 列挙型メンバ名 */ id_enum_mem1, id_enum_mem2 }; /* typedef名 */ typedef struct samp_struct { int samp; } id_typedef; /* 関数名 */ int id_function(struct id_struct_tag *s, union id_union_tag *u, enum id_enum_tag en, id_typedef *t) { printf("%d\n", s->id_struct_mem); printf("%d\n", u->id_union_mem2); printf("%d\n", en); printf("%d\n", t->samp); return s->id_struct_mem; } int main(void) { /* 変数名 */ int id_var = 1; struct id_struct_tag st = {ID_MACRO_NAME1}; union id_union_tag un = {.id_union_mem1 = {0, 1, 0, 0}}; id_typedef ty = {ID_MACRO_NAME2}; id_var = id_function(&st, &un, id_enum_mem2, &ty); if (id_var != 0) { goto id_label; } return EXIT_FAILURE; /* ラベル名 */ id_label: printf("id_label\n"); return EXIT_SUCCESS; }

#include <stdio.h> #include <stdlib.h> /* 関数の宣言(関数プロトタイプ) 引数の識別子のスコープはプロトタイプ内のみ。省略も可能 */ void sampfunc1(const char *p_s); void sampfunc2(int id_i, const char *); /* ファイルスコープとなる変数 p_samp */ const char *p_samp = "file_scope"; void sampfunc1(const char *p_s) { /* 関数スコープ(sampfunc1)となる変数 s */ const char *s = "scope_sampfunc1"; printf("sampfunc1 --- p_s = %s : s = %s : samp_s = %s\n", p_s, s, p_samp); } void sampfunc2(int i, const char *p) { printf("sampfunc2 --- i = %d : p = %s\n", i, p); } int main(void) { /* 関数スコープ(main)となる変数 s */ const char *s = "scope_main"; sampfunc1(s); sampfunc2(2, p_samp); /* 関数スコープとなる変数 i */ int i = -1; /* for文内でのブロックスコープとなる変数 i */ for (int i=0; i < 3; i++) { if (i > 1) { /* ブロック外ラベルへのジャンプ */ goto id_label; } printf("for文ブロック内 --- i = %d\n", i); } return EXIT_FAILURE; /* ラベル(関数スコープ) */ id_label: printf("for文ブロック外 --- i = %d\n", i); printf("id_label\n"); return EXIT_SUCCESS; }

#include <stdio.h> #include <stdlib.h> /* 外部リンケージを持つ変数 */ extern const char *p_samp1; /* 外部リンケージを持つ関数の宣言(extern無し・デフォルト) sampfunc1 */ void sampfunc1(void); /* 内部リンケージを持つ変数 */ static const char *p_samp2 = "sample1.c p_samp2 内部"; /* 外部リンケージを持つ変数 p_samp3 */ const char *p_samp3 = "sample1.c p_samp3 外部"; /* 内部リンケージを持つ関数 sampfunc2 */ static void sampfunc2(void) { printf("[1] sampfunc2 %s : %s\n", p_samp1, p_samp2); } /* 外部リンケージを持つ関数 sampfunc3 */ void sampfunc3(void) { printf("[1] sampfunc3 %s : %s\n", p_samp1, p_samp2); } int main(void) { /* リンケージ無し(関数内でextern無しで宣言) p_samp3 */ const char *p_samp3 = "sample1.c p_samp3 無し"; /* sample1.c内関数の呼び出し */ sampfunc1(); /* sample2.c内関数の呼び出し */ sampfunc2(); /* リンケージ無しのp_samp3を出力 */ printf("[1] main %s\n", p_samp3); return EXIT_SUCCESS; }

#include <stdio.h> #include <stdlib.h> /* 外部リンケージを持つ変数 p_samp1 */ const char *p_samp1 = "sample2.c p_samp1 外部"; /* 内部リンケージを持つ変数 p_samp2 */ static const char *p_samp2 = "sample2.c p_samp2 内部"; /* 外部リンケージを持つ変数 p_samp3 */ extern const char *p_samp3; /* 外部リンケージを持つ関数の宣言(extern付き) sampfunc3 */ extern void sampfunc3(void); /* 内部リンケージを持つ関数 sampfunc2 */ static void sampfunc2(void) { printf("[2] sampfunc2 %s : %s\n", p_samp1, p_samp2); printf("[2] sampfunc2 %s\n", p_samp3); } /* 外部リンケージを持つ関数 sampfunc1 */ void sampfunc1(void) { sampfunc2(); sampfunc3(); printf("[2] sampfunc1 %s : %s\n", p_samp1, p_samp2); }

#include <stdio.h> #include <stdlib.h> /* 構造体タグ名 */ struct id_sample { /* 構造体メンバ名 */ int id_sample; }; int main(void) { /* 通常識別子名 */ struct id_sample id_sample; for (id_sample.id_sample=0; id_sample.id_sample < 3; id_sample.id_sample++) { if (id_sample.id_sample > 1) { /* ラベルへのジャンプ */ goto id_sample; } printf("for文ブロック内 --- id_sample.id_sample = %d\n", id_sample.id_sample); } return EXIT_FAILURE; /* ラベル */ id_sample: printf("ラベル : id_sample\n"); return EXIT_SUCCESS; }