Avoid compiler warnings with MinGW64 GCC 6

* nt/inc/ms-w32.h (execve) [MINGW_W64]: Make the prototype match
the GCC 6 builtin, to avoid warnings.  For more details, see
http://lists.gnu.org/archive/html/emacs-devel/2016-08/msg00721.html.

diff --git a/nt/inc/ms-w32.h b/nt/inc/ms-w32.h
index bb8ae6ad8f912e29c255ff0cf4da839f7ed95067..12cd0810054220886e78472e7b3d798e2e03a050 100644 (file)
--- a/nt/inc/ms-w32.h
+++ b/nt/inc/ms-w32.h
@@ -293,7 +293,16 @@ extern int sys_umask (int);
 #define execvp    _execvp
 #include <stdint.h>            /* for intptr_t */
 extern intptr_t _execvp (const char *, char **);
+#ifdef MINGW_W64
+/* MinGW64 GCC 6 has a builtin execve with the prototype shown below.
+   The return value is wrong, and is a bug in GCC, but using the
+   correct prototype causes GCC to emit warnings.  Fortunately, execve
+   is not used in the MinGW build, but the code that references it is
+   still compiled.  */
+extern int execve (const char *, char * const *, char * const *);
+#else
 extern intptr_t execve (const char *, char * const *, char * const *);
+#endif
 #define fdatasync _commit
 #define fdopen   _fdopen
 #define fsync    _commit