Bug#28560 mysql_upgrade test links /usr/local/mysql/lib libraries

 - Chop off .libs/ part of path if running in non installed builddir
   using libtool


client/mysql_upgrade.c:
  Chop off .libs part of path to avoid executing "non relinked" binaries
  that would use the system installed dynamic libraries instead of the
  newly built ones.

client/mysql_upgrade.c

@@ -342,12 +342,6 @@ static my_bool get_full_path_to_executable(char* path)
 
 /*
   Look for the tool in the same directory as mysql_upgrade.
-
-  When running in a not yet installed build the the program
-  will exist but it need to be invoked via it's libtool wrapper.
-  Check if the found tool can executed and if not look in the
-  directory one step higher up where the libtool wrapper normally
-  is found
 */
 
 static void find_tool(char *tool_path, const char *tool_name)
@@ -385,16 +379,32 @@ static void find_tool(char *tool_path, const char *tool_name)
       path[0]= 0;
     }
   }
-  do
-  {
-    DBUG_PRINT("enter", ("path: %s", path));
 
-    /* Chop off last char(since it might be a /) */
-    path[max((strlen(path)-1), 0)]= 0;
+  DBUG_PRINT("info", ("path: '%s'", path));
 
-    /* Chop off last dir part */
+  /* Chop off binary name (i.e mysql-upgrade) from path */
   dirname_part(path, path);
 
+  /*
+    When running in a not yet installed build and using libtool,
+    the program(mysql_upgrade) will be in .libs/ and executed
+    through a libtool wrapper in order to use the dynamic libraries
+    from this build. The same must be done for the tools(mysql and
+    mysqlcheck). Thus if path ends in .libs/, step up one directory
+    and execute the tools from there
+  */
+  path[max((strlen(path)-1), 0)]= 0;   /* Chop off last / */
+  if (strncmp(path + dirname_length(path), ".libs", 5) == 0)
+  {
+    DBUG_PRINT("info", ("Chopping off .libs from '%s'", path));
+
+    /* Chop off .libs */
+    dirname_part(path, path);
+  }
+
+
+  DBUG_PRINT("info", ("path: '%s'", path));
+
   /* Format name of the tool to search for */
   fn_format(tool_path, tool_name,
             path, "", MYF(MY_REPLACE_DIR));
@@ -406,16 +416,15 @@ static void find_tool(char *tool_path, const char *tool_name)
     die("Can't find '%s'", tool_path);
 
   /*
-      Make sure it can be executed, otherwise try again
-      in higher level directory
+    Make sure it can be executed
   */
-  }
-  while(run_tool(tool_path,
+  if (run_tool(tool_path,
                &ds_tmp, /* Get output from command, discard*/
                "--help",
                "2>&1",
                IF_WIN("> NUL", "> /dev/null"),
-                 NULL));
+               NULL))
+    die("Can't execute '%s'", tool_path);
 
   dynstr_free(&ds_tmp);