Sync trunk and py3k versions of string formatting. Will manually merge into py3k.
diff --git a/Objects/stringlib/formatter.h b/Objects/stringlib/formatter.h
index 3b22181..5cead66 100644
--- a/Objects/stringlib/formatter.h
+++ b/Objects/stringlib/formatter.h
@@ -920,9 +920,12 @@
            format the result. We take care of that later. */
         type = 'g';
 
+#if PY_VERSION_HEX < 0x0301000
     /* 'F' is the same as 'f', per the PEP */
+    /* This is no longer the case in 3.x */
     if (type == 'F')
         type = 'f';
+#endif
 
     val = PyFloat_AsDouble(value);
     if (val == -1.0 && PyErr_Occurred())
@@ -1114,9 +1117,12 @@
            format the result. We take care of that later. */
         type = 'g';
 
+#if PY_VERSION_HEX < 0x03010000
+    /* This is no longer the case in 3.x */
     /* 'F' is the same as 'f', per the PEP */
     if (type == 'F')
         type = 'f';
+#endif
 
     if (precision < 0)
         precision = default_precision;