passing by reference... my darkest enemy
actual reason below:
In your case (without reference) the compiler generates a temporary object (int) for the first argument of your MyApplication constructor. You pass this temporary int to QApplication’s constructor (with int reference), which saves the address of this reference. Once your MyApplication constructor is done the temporary int is destroyed but QApplication still has its address.
/***************************************************************************/
/* */
/* t1load.h */
/* */
/* Type 1 font loader (specification). */
/* */
/* Copyright 1996-2001, 2002, 2004, 2006, 2007 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/* modified, and distributed under the terms of the FreeType project */
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
/* this file you indicate that you have read the license and */
/* understand and accept it fully. */
/* */
/***************************************************************************/
#ifndef __T1LOAD_H__
#define __T1LOAD_H__
#include <ft2build.h>
#include FT_INTERNAL_STREAM_H
#include FT_INTERNAL_POSTSCRIPT_AUX_H
#include FT_MULTIPLE_MASTERS_H
#include "t1parse.h"
FT_BEGIN_HEADER
typedef struct T1_Loader_
{
T1_ParserRec parser; /* parser used to read the stream */
FT_Int num_chars; /* number of characters in encoding */
PS_TableRec encoding_table; /* PS_Table used to store the */
/* encoding character names */
FT_Int num_glyphs;
PS_TableRec glyph_names;
PS_TableRec charstrings;
PS_TableRec swap_table; /* For moving .notdef glyph to index 0. */
FT_Int num_subrs;
PS_TableRec subrs;
FT_Bool fontdata;
FT_UInt keywords_encountered; /* T1_LOADER_ENCOUNTERED_XXX */
} T1_LoaderRec, *T1_Loader;
/* treatment of some keywords differs depending on whether */
/* they precede or follow certain other keywords */
#define T1_PRIVATE ( 1 << 0 )
#define T1_FONTDIR_AFTER_PRIVATE ( 1 << 1 )
FT_LOCAL( FT_Error )
T1_Open_Face( T1_Face face );
#ifndef T1_CONFIG_OPTION_NO_MM_SUPPORT
FT_LOCAL( FT_Error )
T1_Get_Multi_Master( T1_Face face,
FT_Multi_Master* master );
FT_LOCAL_DEF( FT_Error )
T1_Get_MM_Var( T1_Face face,
FT_MM_Var* *master );
FT_LOCAL( FT_Error )
T1_Set_MM_Blend( T1_Face face,
FT_UInt num_coords,
FT_Fixed* coords );
FT_LOCAL( FT_Error )
T1_Set_MM_Design( T1_Face face,
FT_UInt num_coords,
FT_Long* coords );
FT_LOCAL_DEF( FT_Error )
T1_Set_Var_Design( T1_Face face,
FT_UInt num_coords,
FT_Fixed* coords );
FT_LOCAL( void )
T1_Done_Blend( T1_Face face );
#endif /* !T1_CONFIG_OPTION_NO_MM_SUPPORT */
FT_END_HEADER
#endif /* __T1LOAD_H__ */
/* END */