Re: How to patch for: #include <bits/wordsize.h>

[Mansour Moufid <mansourmoufid%gmail.com@localhost>]

> On Sep 13, 2025, at 22:49, Mayuresh <mayuresh%acm.org@localhost> wrote:
> 
> On Sat, Sep 13, 2025 at 11:46:26PM +0200, Roland Illig wrote:
>> This definition cannot be used in conditional inclusion directives from
>> the preprocessor. For example:
> 
> How about this borrowed from wordsize.h itself from Linux:
> 
>    #if defined __x86_64__ && !defined __ILP32__
>    # define __WORDSIZE 64
>    #else
>    # define __WORDSIZE 32
>    #endif
> 
> i.e. are __x86_64__ and __ILP32__ ubiquitous?

It depends on the compiler. I know for sure GCC and Clang support __ILP32__ and __LP64__, so you could do this:

    #if !defined(__WORDSIZE)
      #if defined(__ILP32__)
        #define __WORDSIZE 32
      #else
        #define __WORDSIZE 64
      #endif
    #endif

This also works:

    #if !defined(__WORDSIZE)
      #include <stdint.h>
      #if UINTPTR_MAX == UINT32_MAX
        #define __WORDSIZE 32
      #else
        #define __WORDSIZE 64
      #endif
    #endif