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.
/***************************************************************************/
/* */
/* otvbase.c */
/* */
/* OpenType BASE table validation (body). */
/* */
/* Copyright 2004, 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. */
/* */
/***************************************************************************/
#include "otvalid.h"
#include "otvcommn.h"
/*************************************************************************/
/* */
/* The macro FT_COMPONENT is used in trace mode. It is an implicit */
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
/* messages during execution. */
/* */
#undef FT_COMPONENT
#define FT_COMPONENT trace_otvbase
static void
otv_BaseCoord_validate( FT_Bytes table,
OTV_Validator valid )
{
FT_Bytes p = table;
FT_UInt BaseCoordFormat;
OTV_NAME_ENTER( "BaseCoord" );
OTV_LIMIT_CHECK( 4 );
BaseCoordFormat = FT_NEXT_USHORT( p );
p += 2; /* skip Coordinate */
OTV_TRACE(( " (format %d)\n", BaseCoordFormat ));
switch ( BaseCoordFormat )
{
case 1: /* BaseCoordFormat1 */
break;
case 2: /* BaseCoordFormat2 */
OTV_LIMIT_CHECK( 4 ); /* ReferenceGlyph, BaseCoordPoint */
break;
case 3: /* BaseCoordFormat3 */
OTV_LIMIT_CHECK( 2 );
/* DeviceTable */
otv_Device_validate( table + FT_NEXT_USHORT( p ), valid );
break;
default:
FT_INVALID_FORMAT;
}
OTV_EXIT;
}
static void
otv_BaseTagList_validate( FT_Bytes table,
OTV_Validator valid )
{
FT_Bytes p = table;
FT_UInt BaseTagCount;
OTV_NAME_ENTER( "BaseTagList" );
OTV_LIMIT_CHECK( 2 );
BaseTagCount = FT_NEXT_USHORT( p );
OTV_TRACE(( " (BaseTagCount = %d)\n", BaseTagCount ));
OTV_LIMIT_CHECK( BaseTagCount * 4 ); /* BaselineTag */
OTV_EXIT;
}
static void
otv_BaseValues_validate( FT_Bytes table,
OTV_Validator valid )
{
FT_Bytes p = table;
FT_UInt BaseCoordCount;
OTV_NAME_ENTER( "BaseValues" );
OTV_LIMIT_CHECK( 4 );
p += 2; /* skip DefaultIndex */
BaseCoordCount = FT_NEXT_USHORT( p );
OTV_TRACE(( " (BaseCoordCount = %d)\n", BaseCoordCount ));
OTV_LIMIT_CHECK( BaseCoordCount * 2 );
/* BaseCoord */
for ( ; BaseCoordCount > 0; BaseCoordCount-- )
otv_BaseCoord_validate( table + FT_NEXT_USHORT( p ), valid );
OTV_EXIT;
}
static void
otv_MinMax_validate( FT_Bytes table,
OTV_Validator valid )
{
FT_Bytes p = table;
FT_UInt table_size;
FT_UInt FeatMinMaxCount;
OTV_OPTIONAL_TABLE( MinCoord );
OTV_OPTIONAL_TABLE( MaxCoord );
OTV_NAME_ENTER( "MinMax" );
OTV_LIMIT_CHECK( 6 );
OTV_OPTIONAL_OFFSET( MinCoord );
OTV_OPTIONAL_OFFSET( MaxCoord );
FeatMinMaxCount = FT_NEXT_USHORT( p );
OTV_TRACE(( " (FeatMinMaxCount = %d)\n", FeatMinMaxCount ));
table_size = FeatMinMaxCount * 8 + 6;
OTV_SIZE_CHECK( MinCoord );
if ( MinCoord )
otv_BaseCoord_validate( table + MinCoord, valid );
OTV_SIZE_CHECK( MaxCoord );
if ( MaxCoord )
otv_BaseCoord_validate( table + MaxCoord, valid );
OTV_LIMIT_CHECK( FeatMinMaxCount * 8 );
/* FeatMinMaxRecord */
for ( ; FeatMinMaxCount > 0; FeatMinMaxCount-- )
{
p += 4; /* skip FeatureTableTag */
OTV_OPTIONAL_OFFSET( MinCoord );
OTV_OPTIONAL_OFFSET( MaxCoord );
OTV_SIZE_CHECK( MinCoord );
if ( MinCoord )
otv_BaseCoord_validate( table + MinCoord, valid );
OTV_SIZE_CHECK( MaxCoord );
if ( MaxCoord )
otv_BaseCoord_validate( table + MaxCoord, valid );
}
OTV_EXIT;
}
static void
otv_BaseScript_validate( FT_Bytes table,
OTV_Validator valid )
{
FT_Bytes p = table;
FT_UInt table_size;
FT_UInt BaseLangSysCount;
OTV_OPTIONAL_TABLE( BaseValues );
OTV_OPTIONAL_TABLE( DefaultMinMax );
OTV_NAME_ENTER( "BaseScript" );
OTV_LIMIT_CHECK( 6 );
OTV_OPTIONAL_OFFSET( BaseValues );
OTV_OPTIONAL_OFFSET( DefaultMinMax );
BaseLangSysCount = FT_NEXT_USHORT( p );
OTV_TRACE(( " (BaseLangSysCount = %d)\n", BaseLangSysCount ));
table_size = BaseLangSysCount * 6 + 6;
OTV_SIZE_CHECK( BaseValues );
if ( BaseValues )
otv_BaseValues_validate( table + BaseValues, valid );
OTV_SIZE_CHECK( DefaultMinMax );
if ( DefaultMinMax )
otv_MinMax_validate( table + DefaultMinMax, valid );
OTV_LIMIT_CHECK( BaseLangSysCount * 6 );
/* BaseLangSysRecord */
for ( ; BaseLangSysCount > 0; BaseLangSysCount-- )
{
p += 4; /* skip BaseLangSysTag */
otv_MinMax_validate( table + FT_NEXT_USHORT( p ), valid );
}
OTV_EXIT;
}
static void
otv_BaseScriptList_validate( FT_Bytes table,
OTV_Validator valid )
{
FT_Bytes p = table;
FT_UInt BaseScriptCount;
OTV_NAME_ENTER( "BaseScriptList" );
OTV_LIMIT_CHECK( 2 );
BaseScriptCount = FT_NEXT_USHORT( p );
OTV_TRACE(( " (BaseScriptCount = %d)\n", BaseScriptCount ));
OTV_LIMIT_CHECK( BaseScriptCount * 6 );
/* BaseScriptRecord */
for ( ; BaseScriptCount > 0; BaseScriptCount-- )
{
p += 4; /* skip BaseScriptTag */
/* BaseScript */
otv_BaseScript_validate( table + FT_NEXT_USHORT( p ), valid );
}
OTV_EXIT;
}
static void
otv_Axis_validate( FT_Bytes table,
OTV_Validator valid )
{
FT_Bytes p = table;
FT_UInt table_size;
OTV_OPTIONAL_TABLE( BaseTagList );
OTV_NAME_ENTER( "Axis" );
OTV_LIMIT_CHECK( 4 );
OTV_OPTIONAL_OFFSET( BaseTagList );
table_size = 4;
OTV_SIZE_CHECK( BaseTagList );
if ( BaseTagList )
otv_BaseTagList_validate( table + BaseTagList, valid );
/* BaseScriptList */
otv_BaseScriptList_validate( table + FT_NEXT_USHORT( p ), valid );
OTV_EXIT;
}
FT_LOCAL_DEF( void )
otv_BASE_validate( FT_Bytes table,
FT_Validator ftvalid )
{
OTV_ValidatorRec validrec;
OTV_Validator valid = &validrec;
FT_Bytes p = table;
FT_UInt table_size;
OTV_OPTIONAL_TABLE( HorizAxis );
OTV_OPTIONAL_TABLE( VertAxis );
valid->root = ftvalid;
FT_TRACE3(( "validating BASE table\n" ));
OTV_INIT;
OTV_LIMIT_CHECK( 6 );
if ( FT_NEXT_ULONG( p ) != 0x10000UL ) /* Version */
FT_INVALID_FORMAT;
table_size = 6;
OTV_OPTIONAL_OFFSET( HorizAxis );
OTV_SIZE_CHECK( HorizAxis );
if ( HorizAxis )
otv_Axis_validate( table + HorizAxis, valid );
OTV_OPTIONAL_OFFSET( VertAxis );
OTV_SIZE_CHECK( VertAxis );
if ( VertAxis )
otv_Axis_validate( table + VertAxis, valid );
FT_TRACE4(( "\n" ));
}
/* END */