Remove the macros in PC/pyconfig.h that nowaday compiler must have?

Locked-chess-official · November 12, 2025, 3:41am

Some macros on windows, such as “_W64”, now must have.

If it doesn’t have “_W64” on windows, some project will try another way to handle their implements or error that must have, but after include “<Python.h>”, it will always be defined:

github.com/python/cpython

PC/pyconfig.h

main


      
          /* _W64 is not defined for VC6 or eVC4 */
          #ifndef _W64
          #define _W64
          #endif

It may cause some unexpected result (contain unexpected success). I think that it need to be change to:

#ifdef _W64
#define _Py__W64 _W64
#else
#define _Py__W64
#endif

Locked-chess-official · November 12, 2025, 6:15am

The macro is only used in that file:

PC/pyconfig.h:/* _W64 is not defined for VC6 or eVC4 */ 
PC/pyconfig.h:#ifndef _W64 
PC/pyconfig.h:#define _W64 
PC/pyconfig.h:typedef _W64 int Py_ssize_t;

Not only rename but also adjust the logic are easy.

Locked-chess-official · November 12, 2025, 6:55am

This is the project that might be effect by this mscro defining (need further verification) :

github.com/LMiceOrg/LMiced

eal/lmice_eal_event.h

187a98549


      
          #ifdef _W64
          struct lmice_event_s
          {
              evtfd_t fd;
              char name[32];
          };
          #else
          
          struct lmice_event_s
          {
              evtfd_t   fd;
              int32_t padding;
              char name[32];
          };
          #endif

github.com/jockej/guile-emacs

src/w32heap.c

41120e0f5


      
          #ifndef _W64
          typedef enum _HEAP_INFORMATION_CLASS {
            HeapCompatibilityInformation
          } HEAP_INFORMATION_CLASS;
          
          typedef WINBASEAPI BOOL (WINAPI * HeapSetInformation_Proc)(HANDLE,HEAP_INFORMATION_CLASS,PVOID,SIZE_T);
          #endif
          
          void
          init_heap (void)
          {
            if (using_dynamic_heap)
              {
                unsigned long enable_lfh = 2;
          
                /* After dumping, use a new private heap.  We explicitly enable
                   the low fragmentation heap (LFH) here, for the sake of pre
                   Vista versions.  Note: this will harmlessly fail on Vista and
                   later, where the low-fragmentation heap is enabled by
                   default.  It will also fail on pre-Vista versions when Emacs

This file has been truncated. show original

github.com/LMiceOrg/LMiced

eal/lmice_eal_shm_win.h

187a98549


      
          #ifdef _W64
          struct lmice_shm_s
          {
              shmfd_t     fd;
              uint32_t    size;
              uint32_t    reserved;
              addr_t      addr;
              char        name[32];
          };
          #else
          struct lmice_shm_s
          {
              shmfd_t     fd;
              uint32_t    size;
              addr_t      addr;
              char        name[32];
          };
          #endif

github.com/cyrilarnould/findutils

locate/locate.c

366db5aa9


      
          # ifdef _W64
             int _dowildcard = 0;
          # else
             int _CRT_glob = 0;
          # endif

github.com/PRL-PRG/R-vanilla

src/library/parallel/src/ncpus.c

d8654da3b


      
          #ifndef _W64
          # include "glpi.h"
          #endif

github.com/lxq2537664558/darkplaces

vid_sdl.c

91e898971


      
          #ifndef _W64 //If Windows 64bit data types don't exist
          #ifndef SetClassLongPtr
          #define SetClassLongPtr SetClassLong
          #endif

github.com/droptablestar/cxxr

src/extra/trio/compat.c

8b33e0701


      
          #ifndef _W64
          /* This is needed as MinGW's stdio.h has an inline vnsprintf mapping to
             _vsnprintf: MinGW-w64's maps to __imp__vsnprintf */
          int _vsnprintf(char *buffer, size_t bufferSize, const char *format, va_list args)
          {
              return trio_vsnprintf(buffer, bufferSize, format, args);
          }
          #endif

github.com/AdaCore/e3-core

tools/rlimit/rlimit-NT.c

1f4f4c7e2


      
          #ifndef _W64
          BOOL WINAPI SetInformationJobObject(
            HANDLE             hJob,
            JOBOBJECTINFOCLASS JobObjectInfoClass,
            LPVOID             lpJobObjectInfo,
            DWORD              cbJobObjectInfoLength
          );
          #else
          #define JOB_OBJECT_BREAKAWAY_OK JOB_OBJECT_LIMIT_BREAKAWAY_OK
          #endif