Manual merge, no effect on 4.1.

Build-tools/Do-compile:
  Change in 4.0 was backport, no effect on 4.1
configure.in:
  No change in 4.1 on merging.
sql/item_strfunc.cc:
  No change in 4.1

Build-tools/Do-compile

@@ -7,6 +7,7 @@ use Sys::Hostname;
 @config_options= ();
 @make_options= ();
 
+$opt_comment=$opt_distribution=$opt_user=$opt_config_env=$opt_config_extra_env="";
 $opt_comment=$opt_distribution=$opt_user=$opt_config_env=$opt_config_extra_env="";
 $opt_dbd_options=$opt_perl_options=$opt_config_options=$opt_make_options=$opt_suffix="";
 $opt_tmp=$opt_version_suffix="";

sql/item_strfunc.cc

@@ -1681,12 +1681,12 @@ String *Item_func_format::val_str(String *str)
   if (str_length >= dec+4)
   {
     char *tmp,*pos;
-    length= str->length()+(diff=(str_length- dec-1)/3);
+    length= str->length()+(diff= (int)(str_length- dec-1)/3);
     str= copy_if_not_alloced(&tmp_str,str,length);
     str->length(length);
     tmp= (char*) str->ptr()+length - dec-1;
     for (pos= (char*) str->ptr()+length-1; pos != tmp; pos--)
-      pos[0]= pos[-(int) diff];
+      pos[0]= pos[-diff];
     while (diff)
     {
       *pos= *(pos - diff);