Index: Objects/unicodeobject.c
===================================================================
--- Objects/unicodeobject.c	(révision 82196)
+++ Objects/unicodeobject.c	(copie de travail)
@@ -50,6 +50,30 @@
 #include <windows.h>
 #endif
 
+/* Py_UNICODE* to Py_UCS4 converter */
+#ifdef Py_UNICODE_WIDE
+#define Py_UNICODE_JOIN_LOW_SURROGATE(ucs, pos, size) (void)0
+#else Py_UNICODE_WIDE
+#define Py_UNICODE_JOIN_LOW_SURROGATE(ucs, pos, size)                     \
+do {                                                                      \
+    if (ucs >= 0xD800 && ucs < 0xDC00 && size) {                          \
+        Py_UNICODE ch2 = *(pos);                                          \
+        if (ch2 >= 0xDC00 && ch2 <= 0xDFFF) {                             \
+            ucs = (((ucs & 0x03FF) << 10) | (ch2 & 0x03FF)) + 0x00010000; \
+            (pos)++;                                                      \
+            (size)--;                                                     \
+        }                                                                 \
+    }                                                                     \
+} while (0)
+#endif
+
+#define Py_UNICODE_GET_UCS4_CHAR(ucs, pos, size)                          \
+    do {                                                                  \
+        ucs = *(pos++);                                                   \
+        (size)--;                                                         \
+        Py_UNICODE_JOIN_LOW_SURROGATE(ucs, pos, size);                    \
+    } while (0)
+
 /* Limit for the Unicode object free list */
 
 #define PyUnicode_MAXFREELIST       1024
@@ -2974,18 +2998,9 @@
         iorder[3] = 0;
     }
 
-    while (size-- > 0) {
-        Py_UCS4 ch = *s++;
-#ifndef Py_UNICODE_WIDE
-        if (0xD800 <= ch && ch <= 0xDBFF && size > 0) {
-            Py_UCS4 ch2 = *s;
-            if (0xDC00 <= ch2 && ch2 <= 0xDFFF) {
-                ch = (((ch & 0x3FF)<<10) | (ch2 & 0x3FF)) + 0x10000;
-                s++;
-                size--;
-            }
-        }
-#endif
+    while (size > 0) {
+        Py_UCS4 ch;
+        Py_UNICODE_GET_UCS4_CHAR(ch, s, size);
         STORECHAR(ch);
     }
 
@@ -7672,16 +7687,17 @@
 unicode_isprintable(PyObject *self)
 {
     register const Py_UNICODE *p = PyUnicode_AS_UNICODE(self);
-    register const Py_UNICODE *e;
+    register Py_ssize_t size = PyUnicode_GET_SIZE(self);
+    Py_UCS4 ucs;
 
     /* Shortcut for single character strings */
-    if (PyUnicode_GET_SIZE(self) == 1 && Py_UNICODE_ISPRINTABLE(*p)) {
+    if (size == 1 && Py_UNICODE_ISPRINTABLE(*p)) {
         Py_RETURN_TRUE;
     }
 
-    e = p + PyUnicode_GET_SIZE(self);
-    for (; p < e; p++) {
-        if (!Py_UNICODE_ISPRINTABLE(*p)) {
+    while (size > 0) {
+        Py_UNICODE_GET_UCS4_CHAR(ucs, p, size);
+        if (!Py_UNICODE_ISPRINTABLE(ucs)) {
             Py_RETURN_FALSE;
         }
     }
@@ -8092,20 +8108,9 @@
         else {
             Py_UCS4 ucs = ch;
 
-#ifndef Py_UNICODE_WIDE
-            Py_UNICODE ch2 = 0;
             /* Get code point from surrogate pair */
-            if (size > 0) {
-                ch2 = *s;
-                if (ch >= 0xD800 && ch < 0xDC00 && ch2 >= 0xDC00
-                    && ch2 <= 0xDFFF) {
-                    ucs = (((ch & 0x03FF) << 10) | (ch2 & 0x03FF))
-                        + 0x00010000;
-                    s++;
-                    size--;
-                }
-            }
-#endif
+            Py_UNICODE_JOIN_LOW_SURROGATE(ucs, s, size);
+
             /* Map Unicode whitespace and control characters
                (categories Z* and C* except ASCII space)
             */
@@ -8145,7 +8150,7 @@
                 *p++ = ch;
 #ifndef Py_UNICODE_WIDE
                 if (ucs >= 0x10000)
-                    *p++ = ch2;
+                    *p++ = *s;
 #endif
             }
         }