Nigel@PB-IM2424 ~ $ gcc --version gcc.exe (GCC) 4.5.0 Copyright (C) 2010 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Nigel@PB-IM2424 ~ $ gcc -Wall tracking.c tracking.c: In function 'check_new': tracking.c:22:5: warning: format '%p' expects type 'void *', but argument 2 has type 'uintptr_t' tracking.c:22:5: warning: format '%p' expects type 'void *', but argument 3 has type 'ptrdiff_t' tracking.c: At top level: tracking.c:26:6: warning: return type of 'main' is not 'int' Nigel@PB-IM2424 ~ $ cat tracking.c #include #define __STDC_LIMIT_MACROS #include #include #define ALIGN_BITS ( sizeof(void*) >> __UINT64_C( 1 ) ) #define BIT_BITS __UINT64_C( 3 ) #define BYTE_BITS __UINT64_C( 14 ) #define SLOT_BITS ( sizeof( void*) * 8 ) - ( ALIGN_BITS + BIT_BITS + BYTE_BITS ) #define BYTES_PER_SLOT __UINT64_C( 1 ) << BYTE_BITS #define TRACKING_SLOTS 8192 // max. 8192 for 4GB/32-bit machine int check_new( uintptr_t p ) { ptrdiff_t slot = ( p >> ( ALIGN_BITS + BIT_BITS + BYTE_BITS ) ); ptrdiff_t byte = ( p >> ( ALIGN_BITS + BIT_BITS)) & ( BYTE_BITS - 1 ); ptrdiff_t bit = ( p >> ALIGN_BITS) & ( BIT_BITS - 1 ); ptrdiff_t nop = p & ( ALIGN_BITS - 1 ); printf( "address: %p slot: %p byte: %4x bit: %4x nop:%x\n", p, slot, byte, bit, nop ); return 1; } void main( void ) { uintptr_t p; for( p = __UINT64_C( 123456 ); p < ( __UINT64_C( 1 ) << 34 ); p += ( __UINT64_C( 1 ) << 29 ) ) { check_new( p ); } }