diff --git a/ext/pg_text_decoder.c b/ext/pg_text_decoder.c
index 2e1eb1059..000b61553 100644
--- a/ext/pg_text_decoder.c
+++ b/ext/pg_text_decoder.c
@@ -942,8 +942,8 @@ static VALUE
 init_pg_text_decoder_inet(VALUE rb_mPG_TextDecoder)
 {
 	rb_require("ipaddr");
+	rb_gc_register_address(&s_IPAddr);
 	s_IPAddr = rb_funcall(rb_cObject, rb_intern("const_get"), 1, rb_str_new2("IPAddr"));
-	rb_global_variable(&s_IPAddr);
 	s_ivar_family = rb_intern("@family");
 	s_ivar_addr = rb_intern("@addr");
 	s_ivar_mask_addr = rb_intern("@mask_addr");
@@ -953,10 +953,10 @@ init_pg_text_decoder_inet(VALUE rb_mPG_TextDecoder)
 
 	use_ipaddr_alloc = RTEST(rb_eval_string("IPAddr.new.instance_variables.sort == [:@addr, :@family, :@mask_addr]"));
 
+	rb_gc_register_address(&s_vmasks4);
+	rb_gc_register_address(&s_vmasks6);
 	s_vmasks4 = rb_eval_string("a = [0]*33; a[0] = 0; a[32] = 0xffffffff; 31.downto(1){|i| a[i] = a[i+1] - (1 << (31 - i))}; a.freeze");
-	rb_global_variable(&s_vmasks4);
 	s_vmasks6 = rb_eval_string("a = [0]*129; a[0] = 0; a[128] = 0xffffffffffffffffffffffffffffffff; 127.downto(1){|i| a[i] = a[i+1] - (1 << (127 - i))}; a.freeze");
-	rb_global_variable(&s_vmasks6);
 
 	/* dummy = rb_define_class_under( rb_mPG_TextDecoder, "Inet", rb_cPG_SimpleDecoder ); */
 	pg_define_coder( "Inet", pg_text_dec_inet, rb_cPG_SimpleDecoder, rb_mPG_TextDecoder);
@@ -973,12 +973,12 @@ init_pg_text_decoder(void)
 	s_id_utc = rb_intern("utc");
 	s_id_getlocal = rb_intern("getlocal");
 
+	rb_gc_register_address(&s_nan);
+	rb_gc_register_address(&s_pos_inf);
+	rb_gc_register_address(&s_neg_inf);
 	s_nan = rb_eval_string("0.0/0.0");
-	rb_global_variable(&s_nan);
 	s_pos_inf = rb_eval_string("1.0/0.0");
-	rb_global_variable(&s_pos_inf);
 	s_neg_inf = rb_eval_string("-1.0/0.0");
-	rb_global_variable(&s_neg_inf);
 
 	/* This module encapsulates all decoder classes with text input format */
 	rb_mPG_TextDecoder = rb_define_module_under( rb_mPG, "TextDecoder" );
diff --git a/ext/pg_text_encoder.c b/ext/pg_text_encoder.c
index e1c72972b..e465a15d2 100644
--- a/ext/pg_text_encoder.c
+++ b/ext/pg_text_encoder.c
@@ -381,8 +381,8 @@ pg_text_enc_numeric(t_pg_coder *this, VALUE value, char *out, VALUE *intermediat
 static VALUE
 init_pg_text_encoder_numeric(VALUE rb_mPG_TextDecoder)
 {
+	rb_gc_register_address(&s_str_F);
 	s_str_F = rb_str_freeze(rb_str_new_cstr("F"));
-	rb_global_variable(&s_str_F);
 	rb_funcall(rb_mPG, rb_intern("require_bigdecimal_without_warning"), 0);
 	s_cBigDecimal = rb_const_get(rb_cObject, rb_intern("BigDecimal"));
 
diff --git a/ext/pg_type_map_all_strings.c b/ext/pg_type_map_all_strings.c
index 4b8fc2578..c5d96a4bc 100644
--- a/ext/pg_type_map_all_strings.c
+++ b/ext/pg_type_map_all_strings.c
@@ -125,6 +125,6 @@ init_pg_type_map_all_strings(void)
 	rb_cTypeMapAllStrings = rb_define_class_under( rb_mPG, "TypeMapAllStrings", rb_cTypeMap );
 	rb_define_alloc_func( rb_cTypeMapAllStrings, pg_tmas_s_allocate );
 
-	pg_typemap_all_strings = rb_obj_freeze( rb_funcall( rb_cTypeMapAllStrings, rb_intern("new"), 0 ));
 	rb_gc_register_address( &pg_typemap_all_strings );
+	pg_typemap_all_strings = rb_obj_freeze( rb_funcall( rb_cTypeMapAllStrings, rb_intern("new"), 0 ));
 }