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, 19 insertions, 7 deletions

diff --git a/eval.c b/eval.c
index f2fde81e19..4770327a72 100644
--- a/eval.c
+++ b/eval.c
@@ -11,18 +11,30 @@
 
 **********************************************************************/
 
-#include "internal.h"
+#include "ruby/config.h"
+
+#ifdef HAVE_SYS_PRCTL_H
+#include <sys/prctl.h>
+#endif
+
 #include "eval_intern.h"
-#include "iseq.h"
 #include "gc.h"
-#include "ruby/vm.h"
-#include "vm_core.h"
+#include "internal.h"
+#include "internal/class.h"
+#include "internal/error.h"
+#include "internal/eval.h"
+#include "internal/hash.h"
+#include "internal/inits.h"
+#include "internal/io.h"
+#include "internal/mjit.h"
+#include "internal/object.h"
+#include "internal/variable.h"
+#include "iseq.h"
 #include "mjit.h"
 #include "probes.h"
 #include "probes_helper.h"
-#ifdef HAVE_SYS_PRCTL_H
-#include <sys/prctl.h>
-#endif
+#include "ruby/vm.h"
+#include "vm_core.h"
 
 NORETURN(void rb_raise_jump(VALUE, VALUE));
 void rb_ec_clear_current_thread_trace_func(const rb_execution_context_t *ec);