13 files changed, 153 insertions, 28 deletions

diff --git a/spec/ruby/optional/capi/ext/array_spec.c b/spec/ruby/optional/capi/ext/array_spec.c
index 2347798bb4..628c4df9d7 100644
--- a/spec/ruby/optional/capi/ext/array_spec.c
+++ b/spec/ruby/optional/capi/ext/array_spec.c
@@ -196,6 +196,7 @@ static VALUE copy_ary(RB_BLOCK_CALL_FUNC_ARGLIST(el, new_ary)) {
   return rb_ary_push(new_ary, el);
 }
 
+#ifndef RUBY_VERSION_IS_4_0
 static VALUE array_spec_rb_iterate(VALUE self, VALUE ary) {
   VALUE new_ary = rb_ary_new();
 
@@ -203,6 +204,7 @@ static VALUE array_spec_rb_iterate(VALUE self, VALUE ary) {
 
   return new_ary;
 }
+#endif
 
 static VALUE array_spec_rb_block_call(VALUE self, VALUE ary) {
   VALUE new_ary = rb_ary_new();
@@ -216,6 +218,7 @@ static VALUE sub_pair(RB_BLOCK_CALL_FUNC_ARGLIST(el, holder)) {
   return rb_ary_push(holder, rb_ary_entry(el, 1));
 }
 
+#ifndef RUBY_VERSION_IS_4_0
 static VALUE each_pair(VALUE obj) {
   return rb_funcall(obj, rb_intern("each_pair"), 0);
 }
@@ -227,6 +230,7 @@ static VALUE array_spec_rb_iterate_each_pair(VALUE self, VALUE obj) {
 
   return new_ary;
 }
+#endif
 
 static VALUE array_spec_rb_block_call_each_pair(VALUE self, VALUE obj) {
   VALUE new_ary = rb_ary_new();
@@ -241,10 +245,12 @@ static VALUE iter_yield(RB_BLOCK_CALL_FUNC_ARGLIST(el, ary)) {
   return Qnil;
 }
 
+#ifndef RUBY_VERSION_IS_4_0
 static VALUE array_spec_rb_iterate_then_yield(VALUE self, VALUE obj) {
   rb_iterate(rb_each, obj, iter_yield, obj);
   return Qnil;
 }
+#endif
 
 static VALUE array_spec_rb_block_call_then_yield(VALUE self, VALUE obj) {
   rb_block_call(obj, rb_intern("each"), 0, 0, iter_yield, obj);
@@ -308,9 +314,11 @@ void Init_array_spec(void) {
   rb_define_method(cls, "rb_ary_plus", array_spec_rb_ary_plus, 2);
   rb_define_method(cls, "rb_ary_unshift", array_spec_rb_ary_unshift, 2);
   rb_define_method(cls, "rb_assoc_new", array_spec_rb_assoc_new, 2);
+#ifndef RUBY_VERSION_IS_4_0
   rb_define_method(cls, "rb_iterate", array_spec_rb_iterate, 1);
   rb_define_method(cls, "rb_iterate_each_pair", array_spec_rb_iterate_each_pair, 1);
   rb_define_method(cls, "rb_iterate_then_yield", array_spec_rb_iterate_then_yield, 1);
+#endif
   rb_define_method(cls, "rb_block_call", array_spec_rb_block_call, 1);
   rb_define_method(cls, "rb_block_call_each_pair", array_spec_rb_block_call_each_pair, 1);
   rb_define_method(cls, "rb_block_call_then_yield", array_spec_rb_block_call_then_yield, 1);
diff --git a/spec/ruby/optional/capi/ext/digest_spec.c b/spec/ruby/optional/capi/ext/digest_spec.c
index 9993238cf2..65c8defa20 100644
--- a/spec/ruby/optional/capi/ext/digest_spec.c
+++ b/spec/ruby/optional/capi/ext/digest_spec.c
@@ -135,7 +135,9 @@ VALUE digest_spec_context_size(VALUE self, VALUE meta) {
     return SIZET2NUM(algo->ctx_size);
 }
 
+#ifndef PTR2NUM
 #define PTR2NUM(x) (rb_int2inum((intptr_t)(void *)(x)))
+#endif
 
 VALUE digest_spec_context(VALUE self, VALUE digest) {
     return PTR2NUM(context);
diff --git a/spec/ruby/optional/capi/ext/encoding_spec.c b/spec/ruby/optional/capi/ext/encoding_spec.c
index aa8662cfbd..2038a5d4a8 100644
--- a/spec/ruby/optional/capi/ext/encoding_spec.c
+++ b/spec/ruby/optional/capi/ext/encoding_spec.c
@@ -91,6 +91,11 @@ static VALUE encoding_spec_rb_enc_compatible(VALUE self, VALUE a, VALUE b) {
   return rb_enc_from_encoding(enc);
 }
 
+static VALUE encoding_spec_rb_enc_check(VALUE self, VALUE a, VALUE b) {
+  rb_encoding* enc = rb_enc_check(a, b);
+  return rb_enc_from_encoding(enc);
+}
+
 static VALUE encoding_spec_rb_enc_copy(VALUE self, VALUE dest, VALUE src) {
   rb_enc_copy(dest, src);
   return dest;
@@ -324,6 +329,10 @@ static VALUE encoding_spec_rb_define_dummy_encoding(VALUE self, VALUE name) {
   return INT2NUM(rb_define_dummy_encoding(RSTRING_PTR(name)));
 }
 
+static VALUE encoding_spec_ONIGENC_IS_UNICODE(VALUE self, VALUE encoding) {
+  return ONIGENC_IS_UNICODE(rb_to_encoding(encoding)) ? Qtrue : Qfalse;
+}
+
 void Init_encoding_spec(void) {
   VALUE cls;
   native_rb_encoding_pointer = (rb_encoding**) malloc(sizeof(rb_encoding*));
@@ -349,6 +358,7 @@ void Init_encoding_spec(void) {
   rb_define_method(cls, "rb_enc_associate", encoding_spec_rb_enc_associate, 2);
   rb_define_method(cls, "rb_enc_associate_index", encoding_spec_rb_enc_associate_index, 2);
   rb_define_method(cls, "rb_enc_compatible", encoding_spec_rb_enc_compatible, 2);
+  rb_define_method(cls, "rb_enc_check", encoding_spec_rb_enc_check, 2);
   rb_define_method(cls, "rb_enc_copy", encoding_spec_rb_enc_copy, 2);
   rb_define_method(cls, "rb_enc_codelen", encoding_spec_rb_enc_codelen, 2);
   rb_define_method(cls, "rb_enc_strlen", encoding_spec_rb_enc_strlen, 3);
@@ -384,6 +394,7 @@ void Init_encoding_spec(void) {
   rb_define_method(cls, "ONIGENC_MBC_CASE_FOLD", encoding_spec_ONIGENC_MBC_CASE_FOLD, 1);
   rb_define_method(cls, "rb_enc_left_char_head", encoding_spec_rb_enc_left_char_head, 2);
   rb_define_method(cls, "rb_define_dummy_encoding", encoding_spec_rb_define_dummy_encoding, 1);
+  rb_define_method(cls, "ONIGENC_IS_UNICODE", encoding_spec_ONIGENC_IS_UNICODE, 1);
 }
 
 #ifdef __cplusplus
diff --git a/spec/ruby/optional/capi/ext/gc_spec.c b/spec/ruby/optional/capi/ext/gc_spec.c
index 2637ad27ac..0baa114d7b 100644
--- a/spec/ruby/optional/capi/ext/gc_spec.c
+++ b/spec/ruby/optional/capi/ext/gc_spec.c
@@ -18,6 +18,32 @@ VALUE rb_gc_register_address_outside_init;
 
 VALUE rb_gc_register_mark_object_not_referenced_float;
 
+static VALUE spec_RB_GC_GUARD_keep_alive(VALUE self, VALUE array_with_string) {
+  VALUE string = rb_ary_entry(array_with_string, 0);
+  char* ptr = RSTRING_PTR(string);
+  // Without the RB_GC_GUARD(string) below, string could be GC'd, and ptr become invalid
+  rb_gc();
+  char copy[4];
+  copy[0] = ptr[0];
+  copy[1] = ptr[1];
+  copy[2] = ptr[2];
+  copy[3] = '\0';
+  RB_GC_GUARD(string);
+  return rb_str_new_cstr(copy);
+}
+
+static VALUE spec_RB_GC_GUARD(VALUE self, VALUE object) {
+  RB_GC_GUARD(object);
+  return object;
+}
+
+static VALUE spec_RB_GC_GUARD_raw(VALUE self, VALUE number) {
+  long l = NUM2LONG(number);
+  VALUE value = (VALUE) l;
+  RB_GC_GUARD(value);
+  return Qnil;
+}
+
 static VALUE registered_tagged_address(VALUE self) {
   return registered_tagged_value;
 }
@@ -124,6 +150,9 @@ void Init_gc_spec(void) {
   rb_gc_register_mark_object_not_referenced_float = DBL2NUM(1.61);
   rb_gc_register_mark_object(rb_gc_register_mark_object_not_referenced_float);
 
+  rb_define_method(cls, "RB_GC_GUARD_keep_alive", spec_RB_GC_GUARD_keep_alive, 1);
+  rb_define_method(cls, "RB_GC_GUARD", spec_RB_GC_GUARD, 1);
+  rb_define_method(cls, "RB_GC_GUARD_raw", spec_RB_GC_GUARD_raw, 1);
   rb_define_method(cls, "registered_tagged_address", registered_tagged_address, 0);
   rb_define_method(cls, "registered_reference_address", registered_reference_address, 0);
   rb_define_method(cls, "registered_before_rb_gc_register_address", get_registered_before_rb_gc_register_address, 0);
diff --git a/spec/ruby/optional/capi/ext/io_spec.c b/spec/ruby/optional/capi/ext/io_spec.c
index f3ede15729..fe31cffb49 100644
--- a/spec/ruby/optional/capi/ext/io_spec.c
+++ b/spec/ruby/optional/capi/ext/io_spec.c
@@ -287,6 +287,18 @@ VALUE io_spec_rb_cloexec_open(VALUE self, VALUE path, VALUE flags, VALUE mode) {
   return rb_funcall(rb_cIO, rb_intern("for_fd"), 1, INT2FIX(fd));
 }
 
+VALUE io_spec_rb_cloexec_dup(VALUE self, VALUE io) {
+  int fd = io_spec_get_fd(io);
+  int new_fd = rb_cloexec_dup(fd);
+  return rb_funcall(rb_cIO, rb_intern("for_fd"), 1, INT2FIX(new_fd));
+}
+
+VALUE io_spec_rb_cloexec_fcntl_dupfd(VALUE self, VALUE io, VALUE minfd) {
+  int fd = io_spec_get_fd(io);
+  int new_fd = rb_cloexec_fcntl_dupfd(fd, FIX2INT(minfd));
+  return rb_funcall(rb_cIO, rb_intern("for_fd"), 1, INT2FIX(new_fd));
+}
+
 VALUE io_spec_rb_io_close(VALUE self, VALUE io) {
   return rb_io_close(io);
 }
@@ -319,13 +331,7 @@ static VALUE io_spec_errno_set(VALUE self, VALUE val) {
 
 VALUE io_spec_mode_sync_flag(VALUE self, VALUE io) {
   int mode;
-#ifdef RUBY_VERSION_IS_3_3
   mode = rb_io_mode(io);
-#else
-  rb_io_t *fp;
-  GetOpenFile(io, fp);
-  mode = fp->mode;
-#endif
   if (mode & FMODE_SYNC) {
     return Qtrue;
   } else {
@@ -333,7 +339,6 @@ VALUE io_spec_mode_sync_flag(VALUE self, VALUE io) {
   }
 }
 
-#if defined(RUBY_VERSION_IS_3_3) || defined(TRUFFLERUBY)
 static VALUE io_spec_rb_io_mode(VALUE self, VALUE io) {
   return INT2FIX(rb_io_mode(io));
 }
@@ -360,7 +365,6 @@ static VALUE io_spec_rb_io_open_descriptor(VALUE self, VALUE klass, VALUE descri
 static VALUE io_spec_rb_io_open_descriptor_without_encoding(VALUE self, VALUE klass, VALUE descriptor, VALUE mode, VALUE path, VALUE timeout) {
   return rb_io_open_descriptor(klass, FIX2INT(descriptor), FIX2INT(mode), path, timeout, NULL);
 }
-#endif
 
 void Init_io_spec(void) {
   VALUE cls = rb_define_class("CApiIOSpecs", rb_cObject);
@@ -391,9 +395,10 @@ void Init_io_spec(void) {
   rb_define_method(cls, "rb_io_binmode", io_spec_rb_io_binmode, 1);
   rb_define_method(cls, "rb_fd_fix_cloexec", io_spec_rb_fd_fix_cloexec, 1);
   rb_define_method(cls, "rb_cloexec_open", io_spec_rb_cloexec_open, 3);
+  rb_define_method(cls, "rb_cloexec_dup", io_spec_rb_cloexec_dup, 1);
+  rb_define_method(cls, "rb_cloexec_fcntl_dupfd", io_spec_rb_cloexec_fcntl_dupfd, 2);
   rb_define_method(cls, "errno=", io_spec_errno_set, 1);
   rb_define_method(cls, "rb_io_mode_sync_flag", io_spec_mode_sync_flag, 1);
-#if defined(RUBY_VERSION_IS_3_3) || defined(TRUFFLERUBY)
   rb_define_method(cls, "rb_io_mode", io_spec_rb_io_mode, 1);
   rb_define_method(cls, "rb_io_path", io_spec_rb_io_path, 1);
   rb_define_method(cls, "rb_io_closed_p", io_spec_rb_io_closed_p, 1);
@@ -404,7 +409,6 @@ void Init_io_spec(void) {
   rb_define_const(cls, "FMODE_BINMODE", INT2FIX(FMODE_BINMODE));
   rb_define_const(cls, "FMODE_TEXTMODE", INT2FIX(FMODE_TEXTMODE));
   rb_define_const(cls, "ECONV_UNIVERSAL_NEWLINE_DECORATOR", INT2FIX(ECONV_UNIVERSAL_NEWLINE_DECORATOR));
-#endif
 }
 
 #ifdef __cplusplus
diff --git a/spec/ruby/optional/capi/ext/kernel_spec.c b/spec/ruby/optional/capi/ext/kernel_spec.c
index ff71a7e589..eee324052d 100644
--- a/spec/ruby/optional/capi/ext/kernel_spec.c
+++ b/spec/ruby/optional/capi/ext/kernel_spec.c
@@ -1,4 +1,5 @@
 #include "ruby.h"
+#include "ruby/vm.h"
 #include "rubyspec.h"
 
 #include <errno.h>
@@ -117,9 +118,11 @@ VALUE kernel_spec_rb_eval_string(VALUE self, VALUE str) {
   return rb_eval_string(RSTRING_PTR(str));
 }
 
+#ifndef RUBY_VERSION_IS_4_0
 VALUE kernel_spec_rb_eval_cmd_kw(VALUE self, VALUE cmd, VALUE args, VALUE kw_splat) {
   return rb_eval_cmd_kw(cmd, args, NUM2INT(kw_splat));
 }
+#endif
 
 VALUE kernel_spec_rb_raise(VALUE self, VALUE hash) {
   rb_hash_aset(hash, ID2SYM(rb_intern("stage")), ID2SYM(rb_intern("before")));
@@ -335,6 +338,15 @@ static VALUE kernel_spec_rb_set_end_proc(VALUE self, VALUE io) {
   return Qnil;
 }
 
+static void at_exit_hook(ruby_vm_t *vm) {
+  puts("ruby_vm_at_exit hook ran");
+}
+
+static VALUE kernel_spec_ruby_vm_at_exit(VALUE self) {
+  ruby_vm_at_exit(at_exit_hook);
+  return self;
+}
+
 static VALUE kernel_spec_rb_f_sprintf(VALUE self, VALUE ary) {
   return rb_f_sprintf((int)RARRAY_LEN(ary), RARRAY_PTR(ary));
 }
@@ -403,7 +415,9 @@ void Init_kernel_spec(void) {
   rb_define_method(cls, "rb_category_warn_deprecated_with_integer_extra_value", kernel_spec_rb_category_warn_deprecated_with_integer_extra_value, 1);
   rb_define_method(cls, "rb_ensure", kernel_spec_rb_ensure, 4);
   rb_define_method(cls, "rb_eval_string", kernel_spec_rb_eval_string, 1);
+#ifndef RUBY_VERSION_IS_4_0
   rb_define_method(cls, "rb_eval_cmd_kw", kernel_spec_rb_eval_cmd_kw, 3);
+#endif
   rb_define_method(cls, "rb_raise", kernel_spec_rb_raise, 1);
   rb_define_method(cls, "rb_throw", kernel_spec_rb_throw, 1);
   rb_define_method(cls, "rb_throw_obj", kernel_spec_rb_throw_obj, 2);
@@ -430,6 +444,7 @@ void Init_kernel_spec(void) {
   rb_define_method(cls, "rb_yield_splat", kernel_spec_rb_yield_splat, 1);
   rb_define_method(cls, "rb_exec_recursive", kernel_spec_rb_exec_recursive, 1);
   rb_define_method(cls, "rb_set_end_proc", kernel_spec_rb_set_end_proc, 1);
+  rb_define_method(cls, "ruby_vm_at_exit", kernel_spec_ruby_vm_at_exit, 0);
   rb_define_method(cls, "rb_f_sprintf", kernel_spec_rb_f_sprintf, 1);
   rb_define_method(cls, "rb_str_format", kernel_spec_rb_str_format, 3);
   rb_define_method(cls, "rb_make_backtrace", kernel_spec_rb_make_backtrace, 0);
diff --git a/spec/ruby/optional/capi/ext/rubyspec.h b/spec/ruby/optional/capi/ext/rubyspec.h
index 8aaec36f46..5a92645785 100644
--- a/spec/ruby/optional/capi/ext/rubyspec.h
+++ b/spec/ruby/optional/capi/ext/rubyspec.h
@@ -35,16 +35,16 @@
    (RUBY_API_VERSION_MAJOR == (major) && RUBY_API_VERSION_MINOR < (minor)))
 #define RUBY_VERSION_SINCE(major,minor) (!RUBY_VERSION_BEFORE(major, minor))
 
-#if RUBY_VERSION_SINCE(3, 5)
-#define RUBY_VERSION_IS_3_5
+#if RUBY_VERSION_SINCE(4, 1)
+#define RUBY_VERSION_IS_4_1
 #endif
 
-#if RUBY_VERSION_SINCE(3, 4)
-#define RUBY_VERSION_IS_3_4
+#if RUBY_VERSION_SINCE(4, 0)
+#define RUBY_VERSION_IS_4_0
 #endif
 
-#if RUBY_VERSION_SINCE(3, 3)
-#define RUBY_VERSION_IS_3_3
+#if RUBY_VERSION_SINCE(3, 4)
+#define RUBY_VERSION_IS_3_4
 #endif
 
 #endif
diff --git a/spec/ruby/optional/capi/ext/set_spec.c b/spec/ruby/optional/capi/ext/set_spec.c
index 6535a11be3..11a271b361 100644
--- a/spec/ruby/optional/capi/ext/set_spec.c
+++ b/spec/ruby/optional/capi/ext/set_spec.c
@@ -1,6 +1,7 @@
 #include "ruby.h"
 #include "rubyspec.h"
 
+#ifdef RUBY_VERSION_IS_4_0
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -46,6 +47,7 @@ VALUE set_spec_rb_set_size(VALUE self, VALUE set) {
 
 void Init_set_spec(void) {
   VALUE cls = rb_define_class("CApiSetSpecs", rb_cObject);
+
   rb_define_method(cls, "rb_set_foreach", set_spec_rb_set_foreach, 2);
   rb_define_method(cls, "rb_set_new", set_spec_rb_set_new, 0);
   rb_define_method(cls, "rb_set_new_capa", set_spec_rb_set_new_capa, 1);
@@ -60,3 +62,4 @@ void Init_set_spec(void) {
 }
 #endif
 
+#endif
diff --git a/spec/ruby/optional/capi/ext/string_spec.c b/spec/ruby/optional/capi/ext/string_spec.c
index 094013e049..8291b73ea4 100644
--- a/spec/ruby/optional/capi/ext/string_spec.c
+++ b/spec/ruby/optional/capi/ext/string_spec.c
@@ -12,6 +12,13 @@
 extern "C" {
 #endif
 
+#ifdef PTR2NUM
+#elif SIZEOF_VOIDP <= SIZEOF_LONG
+# define PTR2NUM(x) (LONG2NUM((long)(x)))
+#elif SIZEOF_VOIDP <= SIZEOF_LONG_LONG
+# define PTR2NUM(x) (LL2NUM((LONG_LONG)(x)))
+#endif
+
 /* Make sure the RSTRING_PTR and the bytes are in native memory.
  * On TruffleRuby RSTRING_PTR and the bytes remain in managed memory
  * until they must be written to native memory.
@@ -296,6 +303,26 @@ VALUE string_spec_rb_str_substr(VALUE self, VALUE str, VALUE beg, VALUE len) {
   return rb_str_substr(str, FIX2INT(beg), FIX2INT(len));
 }
 
+VALUE string_spec_rb_str_subpos(VALUE self, VALUE str, VALUE beg) {
+  char* original = RSTRING_PTR(str);
+  char* end = RSTRING_END(str);
+  long len = rb_str_strlen(str);
+  char *p = rb_str_subpos(str, FIX2LONG(beg), &len);
+  if (p == NULL) {
+    return Qnil;
+  }
+
+  if (p >= original && p <= end) {
+    return rb_ary_new_from_args(2, LONG2FIX(p - RSTRING_PTR(str)), LONG2FIX(len));
+  } else {
+    rb_raise(rb_eRuntimeError, "the returned pointer is not inside the original string buffer");
+  }
+}
+
+VALUE string_spec_rb_str_sublen(VALUE self, VALUE str, VALUE pos) {
+  return LONG2FIX(rb_str_sublen(str, FIX2LONG(pos)));
+}
+
 VALUE string_spec_rb_str_to_str(VALUE self, VALUE arg) {
   return rb_str_to_str(arg);
 }
@@ -308,6 +335,11 @@ VALUE string_spec_RSTRING_LENINT(VALUE self, VALUE str) {
   return INT2FIX(RSTRING_LENINT(str));
 }
 
+VALUE string_spec_RSTRING_PTR(VALUE self, VALUE str) {
+  char* ptr = RSTRING_PTR(str);
+  return PTR2NUM(ptr);
+}
+
 VALUE string_spec_RSTRING_PTR_iterate(VALUE self, VALUE str) {
   int i;
   char* ptr;
@@ -393,6 +425,7 @@ VALUE string_spec_RSTRING_PTR_read(VALUE self, VALUE str, VALUE path) {
   if (read(fd, buffer, 30) < 0) {
     rb_syserr_fail(errno, "read");
   }
+  rb_str_set_len(str, 30);
 
   rb_str_modify_expand(str, 53);
   rb_ary_push(capacities, SIZET2NUM(rb_str_capacity(str)));
@@ -531,7 +564,10 @@ static VALUE string_spec_rb_str_modify(VALUE self, VALUE str) {
 }
 
 static VALUE string_spec_rb_utf8_str_new_static(VALUE self) {
-  return rb_utf8_str_new_static("nokogiri", 8);
+  const char* literal = "nokogiri";
+  return rb_ary_new_from_args(2,
+    rb_utf8_str_new_static("nokogiri", 8),
+    PTR2NUM(literal));
 }
 
 static VALUE string_spec_rb_utf8_str_new(VALUE self) {
@@ -581,6 +617,14 @@ static VALUE string_spec_rb_str_to_interned_str(VALUE self, VALUE str) {
   return rb_str_to_interned_str(str);
 }
 
+static VALUE string_spec_rb_interned_str(VALUE self, VALUE str, VALUE len) {
+  return rb_interned_str(RSTRING_PTR(str), FIX2LONG(len));
+}
+
+static VALUE string_spec_rb_interned_str_cstr(VALUE self, VALUE str) {
+  return rb_interned_str_cstr(RSTRING_PTR(str));
+}
+
 void Init_string_spec(void) {
   VALUE cls = rb_define_class("CApiStringSpecs", rb_cObject);
   rb_define_method(cls, "rb_cstr2inum", string_spec_rb_cstr2inum, 2);
@@ -637,9 +681,12 @@ void Init_string_spec(void) {
   rb_define_method(cls, "rb_str_split", string_spec_rb_str_split, 1);
   rb_define_method(cls, "rb_str_subseq", string_spec_rb_str_subseq, 3);
   rb_define_method(cls, "rb_str_substr", string_spec_rb_str_substr, 3);
+  rb_define_method(cls, "rb_str_subpos", string_spec_rb_str_subpos, 2);
+  rb_define_method(cls, "rb_str_sublen", string_spec_rb_str_sublen, 2);
   rb_define_method(cls, "rb_str_to_str", string_spec_rb_str_to_str, 1);
   rb_define_method(cls, "RSTRING_LEN", string_spec_RSTRING_LEN, 1);
   rb_define_method(cls, "RSTRING_LENINT", string_spec_RSTRING_LENINT, 1);
+  rb_define_method(cls, "RSTRING_PTR", string_spec_RSTRING_PTR, 1);
   rb_define_method(cls, "RSTRING_PTR_iterate", string_spec_RSTRING_PTR_iterate, 1);
   rb_define_method(cls, "RSTRING_PTR_iterate_uint32", string_spec_RSTRING_PTR_iterate_uint32, 1);
   rb_define_method(cls, "RSTRING_PTR_short_memcpy", string_spec_RSTRING_PTR_short_memcpy, 1);
@@ -681,6 +728,8 @@ void Init_string_spec(void) {
   rb_define_method(cls, "rb_enc_interned_str_cstr", string_spec_rb_enc_interned_str_cstr, 2);
   rb_define_method(cls, "rb_enc_interned_str", string_spec_rb_enc_interned_str, 3);
   rb_define_method(cls, "rb_str_to_interned_str", string_spec_rb_str_to_interned_str, 1);
+  rb_define_method(cls, "rb_interned_str", string_spec_rb_interned_str, 2);
+  rb_define_method(cls, "rb_interned_str_cstr", string_spec_rb_interned_str_cstr, 1);
 }
 
 #ifdef __cplusplus
diff --git a/spec/ruby/optional/capi/ext/struct_spec.c b/spec/ruby/optional/capi/ext/struct_spec.c
index 413249e828..1c669d153e 100644
--- a/spec/ruby/optional/capi/ext/struct_spec.c
+++ b/spec/ruby/optional/capi/ext/struct_spec.c
@@ -62,7 +62,10 @@ static VALUE struct_spec_rb_struct_size(VALUE self, VALUE st) {
   return rb_struct_size(st);
 }
 
-#if defined(RUBY_VERSION_IS_3_3)
+static VALUE struct_spec_rb_struct_initialize(VALUE self, VALUE st, VALUE values) {
+  return rb_struct_initialize(st, values);
+}
+
 /* Only allow setting three attributes, should be sufficient for testing. */
 static VALUE struct_spec_rb_data_define(VALUE self, VALUE superclass,
   VALUE attr1, VALUE attr2, VALUE attr3) {
@@ -77,7 +80,6 @@ static VALUE struct_spec_rb_data_define(VALUE self, VALUE superclass,
 
   return rb_data_define(superclass, a1, a2, a3, NULL);
 }
-#endif
 
 void Init_struct_spec(void) {
   VALUE cls = rb_define_class("CApiStructSpecs", rb_cObject);
@@ -90,9 +92,8 @@ void Init_struct_spec(void) {
   rb_define_method(cls, "rb_struct_define_under", struct_spec_rb_struct_define_under, 5);
   rb_define_method(cls, "rb_struct_new", struct_spec_rb_struct_new, 4);
   rb_define_method(cls, "rb_struct_size", struct_spec_rb_struct_size, 1);
-#if defined(RUBY_VERSION_IS_3_3)
+  rb_define_method(cls, "rb_struct_initialize", struct_spec_rb_struct_initialize, 2);
   rb_define_method(cls, "rb_data_define", struct_spec_rb_data_define, 4);
-#endif
 }
 
 #ifdef __cplusplus
diff --git a/spec/ruby/optional/capi/ext/thread_spec.c b/spec/ruby/optional/capi/ext/thread_spec.c
index 6ee111b7b7..ac77e4e813 100644
--- a/spec/ruby/optional/capi/ext/thread_spec.c
+++ b/spec/ruby/optional/capi/ext/thread_spec.c
@@ -166,7 +166,7 @@ static VALUE thread_spec_ruby_native_thread_p_new_thread(VALUE self) {
 #endif
 }
 
-#ifdef RUBY_VERSION_IS_3_5
+#ifdef RUBY_VERSION_IS_4_0
 static VALUE thread_spec_ruby_thread_has_gvl_p(VALUE self) {
   return ruby_thread_has_gvl_p() ? Qtrue : Qfalse;
 }
@@ -185,7 +185,7 @@ void Init_thread_spec(void) {
   rb_define_method(cls,  "rb_thread_create", thread_spec_rb_thread_create, 2);
   rb_define_method(cls,  "ruby_native_thread_p", thread_spec_ruby_native_thread_p, 0);
   rb_define_method(cls,  "ruby_native_thread_p_new_thread", thread_spec_ruby_native_thread_p_new_thread, 0);
-#ifdef RUBY_VERSION_IS_3_5
+#ifdef RUBY_VERSION_IS_4_0
   rb_define_method(cls,  "ruby_thread_has_gvl_p", thread_spec_ruby_thread_has_gvl_p, 0);
 #endif
 }
diff --git a/spec/ruby/optional/capi/ext/typed_data_spec.c b/spec/ruby/optional/capi/ext/typed_data_spec.c
index 221f1c8ac4..c6fcfa3bc8 100644
--- a/spec/ruby/optional/capi/ext/typed_data_spec.c
+++ b/spec/ruby/optional/capi/ext/typed_data_spec.c
@@ -106,6 +106,7 @@ VALUE sws_typed_wrap_struct(VALUE self, VALUE val) {
   return TypedData_Wrap_Struct(rb_cObject, &sample_typed_wrapped_struct_data_type, bar);
 }
 
+#ifndef RUBY_VERSION_IS_4_1
 #undef RUBY_UNTYPED_DATA_WARNING
 #define RUBY_UNTYPED_DATA_WARNING 0
 VALUE sws_untyped_wrap_struct(VALUE self, VALUE val) {
@@ -113,6 +114,7 @@ VALUE sws_untyped_wrap_struct(VALUE self, VALUE val) {
   *data = FIX2INT(val);
   return Data_Wrap_Struct(rb_cObject, NULL, free, data);
 }
+#endif
 
 VALUE sws_typed_get_struct(VALUE self, VALUE obj) {
   struct sample_typed_wrapped_struct* bar;
@@ -173,9 +175,11 @@ VALUE sws_typed_rb_check_typeddata_different_type(VALUE self, VALUE obj) {
   return rb_check_typeddata(obj, &sample_typed_wrapped_struct_other_data_type) == DATA_PTR(obj) ? Qtrue : Qfalse;
 }
 
+#ifndef RUBY_VERSION_IS_4_1
 VALUE sws_typed_RTYPEDDATA_P(VALUE self, VALUE obj) {
   return RTYPEDDATA_P(obj) ? Qtrue : Qfalse;
 }
+#endif
 
 void Init_typed_data_spec(void) {
   VALUE cls = rb_define_class("CApiAllocTypedSpecs", rb_cObject);
@@ -183,7 +187,9 @@ void Init_typed_data_spec(void) {
   rb_define_method(cls, "typed_wrapped_data", sdaf_typed_get_struct, 0);
   cls = rb_define_class("CApiWrappedTypedStructSpecs", rb_cObject);
   rb_define_method(cls, "typed_wrap_struct", sws_typed_wrap_struct, 1);
+#ifndef RUBY_VERSION_IS_4_1
   rb_define_method(cls, "untyped_wrap_struct", sws_untyped_wrap_struct, 1);
+#endif
   rb_define_method(cls, "typed_get_struct", sws_typed_get_struct, 1);
   rb_define_method(cls, "typed_get_struct_other", sws_typed_get_struct_different_type, 1);
   rb_define_method(cls, "typed_get_struct_parent", sws_typed_get_struct_parent_type, 1);
@@ -194,10 +200,11 @@ void Init_typed_data_spec(void) {
   rb_define_method(cls, "rb_check_typeddata_same_type", sws_typed_rb_check_typeddata_same_type, 1);
   rb_define_method(cls, "rb_check_typeddata_same_type_parent", sws_typed_rb_check_typeddata_same_type_parent, 1);
   rb_define_method(cls, "rb_check_typeddata_different_type", sws_typed_rb_check_typeddata_different_type, 1);
+#ifndef RUBY_VERSION_IS_4_1
   rb_define_method(cls, "RTYPEDDATA_P", sws_typed_RTYPEDDATA_P, 1);
+#endif
 }
 
 #ifdef __cplusplus
 }
 #endif
-
diff --git a/spec/ruby/optional/capi/ext/util_spec.c b/spec/ruby/optional/capi/ext/util_spec.c
index b5bde420d2..043da99ace 100644
--- a/spec/ruby/optional/capi/ext/util_spec.c
+++ b/spec/ruby/optional/capi/ext/util_spec.c
@@ -20,15 +20,11 @@ VALUE util_spec_rb_scan_args(VALUE self, VALUE argv, VALUE fmt, VALUE expected,
 
   a1 = a2 = a3 = a4 = a5 = a6 = INT2FIX(-1);
 
-#ifdef RB_SCAN_ARGS_KEYWORDS
   if (*RSTRING_PTR(fmt) == 'k') {
     result = rb_scan_args_kw(RB_SCAN_ARGS_KEYWORDS, argc, args, RSTRING_PTR(fmt)+1, &a1, &a2, &a3, &a4, &a5, &a6);
   } else {
-#endif
     result = rb_scan_args(argc, args, RSTRING_PTR(fmt), &a1, &a2, &a3, &a4, &a5, &a6);
-#ifdef RB_SCAN_ARGS_KEYWORDS
   }
-#endif
 
   switch(NUM2INT(expected)) {
   case 6: