do not undef config macros

include/mrbconf.h

@@ -15,10 +15,10 @@
 
 /* -DDISABLE_XXXX to change to drop the feature */
 #define DISABLE_REGEXP	        /* regular expression classes */
-#undef DISABLE_KERNEL_SPRINTF	/* Kernel.sprintf method */
-#undef DISABLE_MATH		/* Math functions */
-#undef DISABLE_TIME		/* Time class */
-#undef DISABLE_STRUCT		/* Struct class */
+//#define DISABLE_SPRINTF	/* Kernel.sprintf method */
+//#define DISABLE_MATH		/* Math functions */
+//#define DISABLE_TIME		/* Time class */
+//#define DISABLE_STRUCT	/* Struct class */
 
 #undef  HAVE_UNISTD_H /* WINDOWS */
 #define HAVE_UNISTD_H /* LINUX */
@@ -38,8 +38,8 @@ typedef intptr_t mrb_sym;
 #ifndef DISABLE_REGEXP
 #define ENABLE_REGEXP
 #endif
-#ifndef DISABLE_KERNEL_SPRINTF
-#define ENABLE_KERNEL_SPRINTF
+#ifndef DISABLE_SPRINTF
+#define ENABLE_SPRINTF
 #endif
 #ifndef DISABLE_MATH
 #define ENABLE_MATH

src/kernel.c

@@ -1168,7 +1168,7 @@ mrb_init_kernel(mrb_state *mrb)
   mrb_define_method(mrb, krn, "singleton_methods",          mrb_obj_singleton_methods_m,     ARGS_ANY());     /* 15.3.1.3.45 */
   mrb_define_method(mrb, krn, "to_s",                       mrb_any_to_s,                    ARGS_NONE());    /* 15.3.1.3.46 */
 
-#ifdef ENABLE_KERNEL_SPRINTF
+#ifdef ENABLE_SPRINTF
   mrb_define_method(mrb, krn, "sprintf",                    mrb_f_sprintf,                   ARGS_ANY());     /* in sprintf.c */
   mrb_define_method(mrb, krn, "format",                     mrb_f_sprintf,                   ARGS_ANY());     /* in sprintf.c */
 #endif

src/sprintf.c

@@ -6,7 +6,7 @@
 
 #include "mruby.h"
 
-#ifdef ENABLE_KERNEL_SPRINTF
+#ifdef ENABLE_SPRINTF
 
 #include <stdio.h>
 #include <string.h>
@@ -1084,4 +1084,4 @@ fmt_setup(char *buf, size_t size, int c, int flags, int width, int prec)
     *buf = '\0';
 }
 
-#endif	/* ENABLE_KERNEL_SPRINTF */
+#endif	/* ENABLE_SPRINTF */