decouple internal.h headers

Saves comitters' daily life by avoid #include-ing everything from
internal.h to make each file do so instead.  This would significantly
speed up incremental builds.

We take the following inclusion order in this changeset:

1.  "ruby/config.h", where _GNU_SOURCE is defined (must be the very
    first thing among everything).
2.  RUBY_EXTCONF_H if any.
3.  Standard C headers, sorted alphabetically.
4.  Other system headers, maybe guarded by #ifdef
5.  Everything else, sorted alphabetically.

Exceptions are those win32-related headers, which tend not be self-
containing (headers have inclusion order dependencies).

1 files changed, 8 insertions, 5 deletions

diff --git a/util.c b/util.c
index aa8e7ef3f2..08dbed105e 100644
--- a/util.c
+++ b/util.c
@@ -10,21 +10,24 @@
 **********************************************************************/
 
 #if defined __MINGW32__ || defined __MINGW64__
-#define MINGW_HAS_SECURE_API 1
+# define MINGW_HAS_SECURE_API 1
 #endif
 
-#include "internal.h"
+#include "ruby/config.h"
 
 #include <ctype.h>
-#include <stdio.h>
 #include <errno.h>
-#include <math.h>
 #include <float.h>
+#include <math.h>
+#include <stdio.h>
 
 #ifdef _WIN32
-#include "missing/file.h"
+# include "missing/file.h"
 #endif
 
+#include "internal.h"
+#include "internal/sanitizers.h"
+#include "internal/util.h"
 #include "ruby/util.h"
 
 const char ruby_hexdigits[] = "0123456789abcdef0123456789ABCDEF";