Size of primitive types in C language on different platforms

I am working on the project which is written in C and can be compiled and run on a variety of platforms. Of course I see a lot of compatibility issues. In order to be better prepared for them I write a simple program which just prints the sizes of primitive types.

Here is the program itself:

#include <stdio.h>

int main(int argc, char* argv[])
{
        printf("sizeof(char)=%ld\n", sizeof(char));
        printf("sizeof(wchar_t)=%ld\n", sizeof(wchar_t));
        printf("sizeof(short)=%ld\n", sizeof(short));
        printf("sizeof(int)=%ld\n", sizeof(int));
        printf("sizeof(long)=%ld\n", sizeof(long));
        printf("sizeof(long long)=%ld\n", sizeof(long long));
        printf("sizeof(void*)=%ld\n", sizeof(void*));
        printf("sizeof(size_t)=%ld\n", sizeof(size_t));
}

Results are below. In case of 32 platforms, everything is clear. Things become more interesting in case of 64 platforms...

Visual C, Win32:

sizeof(char)=1
sizeof(wchar_t)=2
sizeof(short)=2
sizeof(int)=4
sizeof(long)=4
sizeof(long long)=8
sizeof(void*)=4
sizeof(size_t)=4

Visual C, Win64:
sizeof(char)=1
sizeof(wchar_t)=2
sizeof(short)=2
sizeof(int)=4
sizeof(long)=4
sizeof(long long)=8
sizeof(void*)=8
sizeof(size_t)=8

Note that size_t on Win64 takes 8 bytes. This means that the code like
int temp = strlen("temp");
may now generate warning like "conversion from 'size_t' to 'int', possible loss of data". The warning will be generated if type of temp is changed to unsigned int, long or unsigned long.

IBM XL C compiler (on AIX):

sizeof(char)=1
sizeof(wchar_t)=2
sizeof(short)=2
sizeof(int)=4
sizeof(long)=4
sizeof(long long)=8
sizeof(void*)=4
sizeof(size_t)=4

IBM xlc compiler, with -q64 switch:

sizeof(char)=1
sizeof(wchar_t)=4
sizeof(short)=2
sizeof(int)=4
sizeof(long)=8
sizeof(long long)=8
sizeof(void*)=8
sizeof(size_t)=8

Note that long on 64 platform is 8 bytes unlike the Microsoft Visual C. Another interesting fact is that size of wchar_t depends on 32/64 mode as well.

HP-UX C compiler:

sizeof(char)=1
sizeof(wchar_t)=4
sizeof(short)=2
sizeof(int)=4
sizeof(long)=4
sizeof(long long)=8
sizeof(void*)=4
sizeof(size_t)=4

HP-UX C compiler, with +DD64 switch:

sizeof(char)=1
sizeof(wchar_t)=4
sizeof(short)=2
sizeof(int)=4
sizeof(long)=8
sizeof(long long)=8
sizeof(void*)=8
sizeof(size_t)=8

By default this compiler does not recognize wchar_t type. To use it, I have to include additional file <whcar.h>. Unlike IBM, the size of wchar_t is 4 in both versions.

GCC on 32 platform:

sizeof(char)=1
sizeof(wchar_t)=4
sizeof(short)=2
sizeof(int)=4
sizeof(long)=4
sizeof(long long)=8
sizeof(void*)=4
sizeof(size_t)=4

GCC on 64 platform:

sizeof(char)=1
sizeof(wchar_t)=4
sizeof(short)=2
sizeof(int)=4
sizeof(long)=8
sizeof(long long)=8
sizeof(void*)=8
sizeof(size_t)=8

Sun Studio 12 C Compiler:

sizeof(char)=1
sizeof(wchar_t)=4
sizeof(short)=2
sizeof(int)=4
sizeof(long)=4
sizeof(long long)=8
sizeof(void*)=4
sizeof(size_t)=4

Sun Studio 12 C Compiler with -m64 switch:

sizeof(char)=1
sizeof(wchar_t)=4
sizeof(short)=2
sizeof(int)=4
sizeof(long)=8
sizeof(long long)=8
sizeof(void*)=8
sizeof(size_t)=8

Note: as above, additional #include <wchar.h> ir required for wchar_t.