api/tesseractmain: Fix memory leak caused by exit()

When exit() is called from ParseArgs(), no destructors are executed
for the auto variables vars_vec and vars_values.

Making both variables static fixes the memory leaks, because now the
destructors are always executed.

Signed-off-by: Stefan Weil <sw@weilnetz.de>

api/tesseractmain.cpp

@@ -358,16 +358,22 @@ void PreloadRenderers(tesseract::TessBaseAPI* api,
  *  main()
  *
  **********************************************************************/
+
+
 int main(int argc, char **argv) {
   const char* lang = "eng";
   const char* image = NULL;
   const char* outputbase = NULL;
   const char* datapath = NULL;
   bool list_langs = false;
   bool print_parameters = false;
-  GenericVector<STRING> vars_vec, vars_values;
   int arg_i = 1;
   tesseract::PageSegMode pagesegmode = tesseract::PSM_AUTO;
+  /* main() calls functions like ParseArgs which call exit().
+   * This results in memory leaks if vars_vec and vars_values are
+   * declared as auto variables (destructor is not called then). */
+  static GenericVector<STRING> vars_vec;
+  static GenericVector<STRING> vars_values;
 
 #if defined(HAVE_TIFFIO_H) && defined(_WIN32)
   /* Show libtiff warnings on console (not in GUI). */