Patch for warnings in 64bit Windows builds

Patch for warnings in 64bit Windows builds

[Andy Moreton]

Hi,

The 64bit Windows builds have shown a few warnings for some time:

../../src/w32proc.c: In function 'w32_compare_strings':
../../src/w32proc.c:3526:20: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
    pCompareStringW = GetProcAddress (LoadLibrary ("Unicows.dll"),
                    ^
../../src/w32fns.c: In function 'Ffile_system_info':
../../src/w32fns.c:7827:9: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
       = GetProcAddress (hKernel, "GetDiskFreeSpaceExW");
         ^
../../src/w32fns.c:7830:9: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
       = GetProcAddress (hKernel, "GetDiskFreeSpaceExA");
         ^
The following patch builds cleanly on:
  - 32bit mingw
  - 32bit mingw --with-wide-int
  - 64bit mingw64

I don't have copyright paperwork on file, so please let me know if that
is required.

    AndyM

diff --git a/src/w32fns.c b/src/w32fns.c
index abfa315e2a96..499450f4c927 100644
--- a/src/w32fns.c
+++ b/src/w32fns.c
@@ -7799,6 +7799,11 @@ The following %-sequences are provided:
 
 \f
 #ifdef WINDOWSNT
+typedef BOOL (WINAPI *GetDiskFreeSpaceExW_Proc)
+  (LPCWSTR, PULARGE_INTEGER, PULARGE_INTEGER, PULARGE_INTEGER);
+typedef BOOL (WINAPI *GetDiskFreeSpaceExA_Proc)
+  (LPCSTR, PULARGE_INTEGER, PULARGE_INTEGER, PULARGE_INTEGER);
+
 DEFUN ("file-system-info", Ffile_system_info, Sfile_system_info, 1, 1, 0,
        doc: /* Return storage information about the file system FILENAME is on.
 Value is a list of floats (TOTAL FREE AVAIL), where TOTAL is the total
@@ -7822,12 +7827,10 @@ If the underlying system call fails, value is nil.  */)
      added rather late on.  */
   {
     HMODULE hKernel = GetModuleHandle ("kernel32");
-    BOOL (WINAPI *pfn_GetDiskFreeSpaceExW)
-      (wchar_t *, PULARGE_INTEGER, PULARGE_INTEGER, PULARGE_INTEGER)
-      = GetProcAddress (hKernel, "GetDiskFreeSpaceExW");
-    BOOL (WINAPI *pfn_GetDiskFreeSpaceExA)
-      (char *, PULARGE_INTEGER, PULARGE_INTEGER, PULARGE_INTEGER)
-      = GetProcAddress (hKernel, "GetDiskFreeSpaceExA");
+    GetDiskFreeSpaceExW_Proc pfn_GetDiskFreeSpaceExW =
+      (GetDiskFreeSpaceExW_Proc) GetProcAddress (hKernel, "GetDiskFreeSpaceExW");
+    GetDiskFreeSpaceExA_Proc pfn_GetDiskFreeSpaceExA =
+      (GetDiskFreeSpaceExA_Proc) GetProcAddress (hKernel, "GetDiskFreeSpaceExA");
     bool have_pfn_GetDiskFreeSpaceEx =
       ((w32_unicode_filenames && pfn_GetDiskFreeSpaceExW)
        || (!w32_unicode_filenames && pfn_GetDiskFreeSpaceExA));
diff --git a/src/w32proc.c b/src/w32proc.c
index ca4322b69d16..66a9761ad138 100644
--- a/src/w32proc.c
+++ b/src/w32proc.c
@@ -3327,16 +3327,16 @@ yield nil.  */)
   (Lisp_Object cp)
 {
   CHARSETINFO info;
-  DWORD dwcp;
+  DWORD_PTR dwcp;
 
   CHECK_NUMBER (cp);
 
   if (!IsValidCodePage (XINT (cp)))
     return Qnil;
 
-  /* Going through a temporary DWORD variable avoids compiler warning
+  /* Going through a temporary DWORD_PTR variable avoids compiler warning
      about cast to pointer from integer of different size, when
-     building --with-wide-int.  */
+     building --with-wide-int or building for 64bit.  */
   dwcp = XINT (cp);
   if (TranslateCharsetInfo ((DWORD *) dwcp, &info, TCI_SRCCODEPAGE))
     return make_number (info.ciCharset);
@@ -3499,6 +3499,9 @@ get_lcid (const char *locale_name)
 # define LINGUISTIC_IGNORECASE  0x00000010
 #endif
 
+typedef int (WINAPI *CompareStringW_Proc)
+  (LCID, DWORD, LPCWSTR, int, LPCWSTR, int);
+
 int
 w32_compare_strings (const char *s1, const char *s2, char *locname,
 		     int ignore_case)
@@ -3507,7 +3510,7 @@ w32_compare_strings (const char *s1, const char *s2, char *locname,
   wchar_t *string1_w, *string2_w;
   int val, needed;
   extern BOOL g_b_init_compare_string_w;
-  static int (WINAPI *pCompareStringW)(LCID, DWORD, LPCWSTR, int, LPCWSTR, int);
+  static CompareStringW_Proc pCompareStringW;
   DWORD flags = 0;
 
   USE_SAFE_ALLOCA;
@@ -3523,8 +3526,9 @@ w32_compare_strings (const char *s1, const char *s2, char *locname,
     {
       if (os_subtype == OS_9X)
 	{
-	  pCompareStringW = GetProcAddress (LoadLibrary ("Unicows.dll"),
-					    "CompareStringW");
+	  pCompareStringW =
+            (CompareStringW_Proc) GetProcAddress (LoadLibrary ("Unicows.dll"),
+                                                  "CompareStringW");
 	  if (!pCompareStringW)
 	    {
 	      errno = EINVAL;

Re: Patch for warnings in 64bit Windows builds

[Eli Zaretskii]

> From: Andy Moreton <andrewjmoreton@gmail.com>
> Date: Tue, 28 Jul 2015 12:57:42 +0100
> 
> The 64bit Windows builds have shown a few warnings for some time:
> 
> ../../src/w32proc.c: In function 'w32_compare_strings':
> ../../src/w32proc.c:3526:20: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
>     pCompareStringW = GetProcAddress (LoadLibrary ("Unicows.dll"),
>                     ^
> ../../src/w32fns.c: In function 'Ffile_system_info':
> ../../src/w32fns.c:7827:9: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
>        = GetProcAddress (hKernel, "GetDiskFreeSpaceExW");
>          ^
> ../../src/w32fns.c:7830:9: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
>        = GetProcAddress (hKernel, "GetDiskFreeSpaceExA");
>          ^
> The following patch builds cleanly on:
>   - 32bit mingw
>   - 32bit mingw --with-wide-int
>   - 64bit mingw64

Thanks, pushed.

> I don't have copyright paperwork on file, so please let me know if that
> is required.

Not needed, but you are encouraged to start the paperwork rolling, so
it will be ready for your next contribution.

Re: Patch for warnings in 64bit Windows builds

[Andy Moreton]

On Tue 28 Jul 2015, Eli Zaretskii wrote:

>> From: Andy Moreton <andrewjmoreton@gmail.com>
>> Date: Tue, 28 Jul 2015 12:57:42 +0100
>> 
>> The 64bit Windows builds have shown a few warnings for some time:
>> 
>> ../../src/w32proc.c: In function 'w32_compare_strings':
>> ../../src/w32proc.c:3526:20: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
>>     pCompareStringW = GetProcAddress (LoadLibrary ("Unicows.dll"),
>>                     ^
>> ../../src/w32fns.c: In function 'Ffile_system_info':
>> ../../src/w32fns.c:7827:9: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
>>        = GetProcAddress (hKernel, "GetDiskFreeSpaceExW");
>>          ^
>> ../../src/w32fns.c:7830:9: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
>>        = GetProcAddress (hKernel, "GetDiskFreeSpaceExA");
>>          ^
>> The following patch builds cleanly on:
>>   - 32bit mingw
>>   - 32bit mingw --with-wide-int
>>   - 64bit mingw64
>
> Thanks, pushed.

I've noticed some other warnings in the 64bit mingw64 builds requiring
a similar fix:

../../src/w32.c: In function 'maybe_load_unicows_dll':
../../src/w32.c:9174:25: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
    pMultiByteToWideChar = GetProcAddress (ret, "MultiByteToWideChar");
                         ^
../../src/w32.c:9175:25: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
    pWideCharToMultiByte = GetProcAddress (ret, "WideCharToMultiByte");
                         ^

There is also a warning about socket handling:

../../src/w32.c: In function 'sys_socket':
../../src/w32.c:7336:14: warning: overflow in implicit constant conversion [-Woverflow]
       return INVALID_SOCKET;
              ^
c:/msys64/mingw64/x86_64-w64-mingw32/include/psdk_inc/_socket_types.h
contains:

        #if 1
        typedef UINT_PTR	SOCKET;
        #else
        typedef INT_PTR		SOCKET;
        #endif

        #define INVALID_SOCKET	(SOCKET)(~0)

Thus it is corect to warn about a conversion from unsigned 64bit to a
signed 32bit value.

>> I don't have copyright paperwork on file, so please let me know if that
>> is required.
>
> Not needed, but you are encouraged to start the paperwork rolling, so
> it will be ready for your next contribution.

Where do I find the appropriate forms ?

    AndyM

Re: Patch for warnings in 64bit Windows builds

[Eli Zaretskii]

> From: Andy Moreton <andrewjmoreton@gmail.com>
> Date: Thu, 30 Jul 2015 22:09:51 +0100
> 
> I've noticed some other warnings in the 64bit mingw64 builds requiring
> a similar fix:
> 
> ../../src/w32.c: In function 'maybe_load_unicows_dll':
> ../../src/w32.c:9174:25: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
>     pMultiByteToWideChar = GetProcAddress (ret, "MultiByteToWideChar");
>                          ^
> ../../src/w32.c:9175:25: warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]
>     pWideCharToMultiByte = GetProcAddress (ret, "WideCharToMultiByte");
>                          ^
> 
> There is also a warning about socket handling:
> 
> ../../src/w32.c: In function 'sys_socket':
> ../../src/w32.c:7336:14: warning: overflow in implicit constant conversion [-Woverflow]
>        return INVALID_SOCKET;
>               ^
> c:/msys64/mingw64/x86_64-w64-mingw32/include/psdk_inc/_socket_types.h
> contains:
> 
>         #if 1
>         typedef UINT_PTR	SOCKET;
>         #else
>         typedef INT_PTR		SOCKET;
>         #endif
> 
>         #define INVALID_SOCKET	(SOCKET)(~0)
> 
> Thus it is corect to warn about a conversion from unsigned 64bit to a
> signed 32bit value.

Please propose changes to eliminate those.  (I can propose them
myself, but I cannot test them.)

> >> I don't have copyright paperwork on file, so please let me know if that
> >> is required.
> >
> > Not needed, but you are encouraged to start the paperwork rolling, so
> > it will be ready for your next contribution.
> 
> Where do I find the appropriate forms ?

One place is in Gnulib's Git repository, in the doc/Copyright/
directory.  You want the file request-assign.future.  There are some
explanations in
https://www.gnu.org/prep/maintain/html_node/Copyright-Papers.html, but
the form is pretty much self-explanatory.

Thanks.