Fix compilation warnings on MS-Windows

* src/w32.c (_ANONYMOUS_UNION, _ANONYMOUS_STRUCT): Remove
definitions of these macros, which seem to be unneeded and cause
compiler warnings.
* src/fileio.c (NOMINMAX): Avoid compiler warnings about unused
macros.
* src/firstfile.c (dummy_main_reference): Rename from 'dummy' and
make it external, to avoid compiler warning.

3 files changed, 6 insertions, 11 deletions

diff --git a/src/fileio.c b/src/fileio.c
index 8f16d1e8496..6026d8ebad4 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -60,6 +60,10 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #ifdef WINDOWSNT
 #define NOMINMAX 1
 #include <windows.h>
+/* The redundant #ifdef is to avoid compiler warning about unused macro.  */
+#ifdef NOMINMAX
+#undef NOMINMAX
+#endif
 #include <sys/file.h>
 #include "w32.h"
 #endif /* not WINDOWSNT */
diff --git a/src/firstfile.c b/src/firstfile.c
index 188d4f81b5c..962d6f6c7f6 100644
--- a/src/firstfile.c
+++ b/src/firstfile.c
@@ -26,7 +26,7 @@ char my_begbss[1];  /* Do not initialize this variable.  */
 static char _my_begbss[1];
 char * my_begbss_static = _my_begbss;
 
-/* Add a dummy reference to ensure emacs.obj is linked in.  */
+/* Add a dummy reference to ensure emacs.o is linked in.  */
 extern int main (int, char **);
-static int (*dummy) (int, char **) = main;
+int (*dummy_main_reference) (int, char **) = main;
 #endif
diff --git a/src/w32.c b/src/w32.c
index 517e286eaa9..ad7d94a21d2 100644
--- a/src/w32.c
+++ b/src/w32.c
@@ -94,13 +94,6 @@ extern void dynlib_reset_last_error (void);
 #include <pwd.h>
 #include <grp.h>
 
-/* MinGW64 defines these in its _mingw.h.  */
-#ifndef _ANONYMOUS_UNION
-# define _ANONYMOUS_UNION
-#endif
-#ifndef _ANONYMOUS_STRUCT
-# define _ANONYMOUS_STRUCT
-#endif
 #include <windows.h>
 /* Some versions of compiler define MEMORYSTATUSEX, some don't, so we
    use a different name to avoid compilation problems.  */
@@ -282,8 +275,6 @@ extern int sys_select (int, SELECT_TYPE *, SELECT_TYPE *, SELECT_TYPE *,
                        struct timespec *, void *);
 extern int sys_dup (int);
 
-
-
 
 /* Initialization states.