fixed length data types in C/C++

Question

I\'ve heard that size of data types such as int may vary across platforms.

My first question is: can someone bring some example, what goes wrong, when p

Answer 1

For the first question: Integer Overflow.

For the second question: for example, to typedef an unsigned 32 bits integer, on a platform where int is 4 bytes, use:

 typedef unsigned int u32;

On a platform where int is 2 bytes while long is 4 bytes:

typedef unsigned long u32;

In this way, you only need to modify one header file to make the types cross-platform.

If there are some platform-specific macros, this can be achieved without modifying manually:

#if defined(PLAT1)
typedef unsigned int u32;
#elif defined(PLAT2)
typedef unsigned long u32;
#endif

If C99 stdint.h is supported, it's preferred.