bpo-40268: Remove unused osdefs.h includes (pythonGH-19532)

When the include is needed, add required symbol in a comment.

Author: vstinner

Modules/_tracemalloc.c

@@ -4,7 +4,6 @@
 #include "pycore_traceback.h"
 #include "hashtable.h"
 #include "frameobject.h"
-#include "osdefs.h"
 
 #include "clinic/_tracemalloc.c.h"
 /*[clinic input]

Modules/getpath.c

@@ -4,7 +4,7 @@
 #include "pycore_fileutils.h"
 #include "pycore_initconfig.h"
 #include "pycore_pathconfig.h"
-#include "osdefs.h"
+#include "osdefs.h"               // DELIM
 
 #include <sys/types.h>
 #include <string.h>

Modules/posixmodule.c

@@ -312,11 +312,11 @@ extern char        *ctermid_r(char *);
 #ifndef IO_REPARSE_TAG_MOUNT_POINT
 #define IO_REPARSE_TAG_MOUNT_POINT (0xA0000003L)
 #endif
-#include "osdefs.h"
+#include "osdefs.h"               // SEP
 #include <malloc.h>
 #include <windows.h>
-#include <shellapi.h>   /* for ShellExecute() */
-#include <lmcons.h>     /* for UNLEN */
+#include <shellapi.h>             // ShellExecute()
+#include <lmcons.h>               // UNLEN
 #define HAVE_SYMLINK
 #endif /* _MSC_VER */
 

Modules/syslogmodule.c

@@ -50,7 +50,7 @@ Revision history:
 /* syslog module */
 
 #include "Python.h"
-#include "osdefs.h"
+#include "osdefs.h"               // SEP
 
 #include <syslog.h>
 

Objects/exceptions.c

@@ -9,7 +9,7 @@
 #include "pycore_initconfig.h"
 #include "pycore_object.h"
 #include "structmember.h"         // PyMemberDef
-#include "osdefs.h"
+#include "osdefs.h"               // SEP
 
 
 /* Compatibility aliases */
@@ -1435,11 +1435,13 @@ my_basename(PyObject *name)
     size = PyUnicode_GET_LENGTH(name);
     offset = 0;
     for(i=0; i < size; i++) {
-        if (PyUnicode_READ(kind, data, i) == SEP)
+        if (PyUnicode_READ(kind, data, i) == SEP) {
             offset = i + 1;
+        }
     }
-    if (offset != 0)
+    if (offset != 0) {
         return PyUnicode_Substring(name, offset, size);
+    }
     else {
         Py_INCREF(name);
         return name;

PC/getpathp.c

@@ -80,9 +80,9 @@
 
 
 #include "Python.h"
-#include "pycore_initconfig.h"   /* PyStatus */
-#include "pycore_pathconfig.h"   /* _PyPathConfig */
-#include "osdefs.h"
+#include "pycore_initconfig.h"    // PyStatus
+#include "pycore_pathconfig.h"    // _PyPathConfig
+#include "osdefs.h"               // SEP, ALTSEP
 #include <wchar.h>
 
 #ifndef MS_WINDOWS

Python/fileutils.c

@@ -1,6 +1,6 @@
 #include "Python.h"
 #include "pycore_fileutils.h"
-#include "osdefs.h"
+#include "osdefs.h"               // SEP
 #include <locale.h>
 
 #ifdef MS_WINDOWS

Python/import.c

@@ -16,7 +16,6 @@
 #include "marshal.h"
 #include "code.h"
 #include "frameobject.h"
-#include "osdefs.h"
 #include "importdl.h"
 #include "pydtrace.h"
 

Python/pathconfig.c

@@ -1,7 +1,7 @@
 /* Path configuration like module_search_path (sys.path) */
 
 #include "Python.h"
-#include "osdefs.h"
+#include "osdefs.h"               // DELIM
 #include "pycore_initconfig.h"
 #include "pycore_fileutils.h"
 #include "pycore_pathconfig.h"

Python/pylifecycle.c

@@ -26,7 +26,6 @@
 #include "symtable.h"
 #include "ast.h"
 #include "marshal.h"
-#include "osdefs.h"
 #include <locale.h>
 
 #ifdef HAVE_SIGNAL_H