win32: fixes to build on Windows/MSYS2/mingw-w64

To investigate GitHub issue #200 it was necessary to perform
build on Window using the MSYS2/mingw-w64 toolchain.  This
threw up some issues:

- The settings for _WIN32_WINNT and __USE_MINGW_ANSI_STDIO differ
  from those in Fedora resulting in compiler errors and warnings.
  Force the defaults I'm used to.

- The workaround to allow native compilation of mconf.c was broken
  by a subsequent upstream change.  Make it work again.

4 files changed, 8 insertions, 6 deletions

diff --git a/include/libbb.h b/include/libbb.h
index c4734e86d..5e1d1fc5b 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -144,9 +144,6 @@
 #elif defined __APPLE__
 # include <netinet/in.h>
 #elif ENABLE_PLATFORM_MINGW32
-# ifndef WINVER
-#  define WINVER 0x0501
-# endif
 # include <winsock2.h>
 # include <ws2tcpip.h>
 #else
diff --git a/include/platform.h b/include/platform.h
index ea97d2682..0fc270fab 100644
--- a/include/platform.h
+++ b/include/platform.h
@@ -10,6 +10,11 @@
 #if ENABLE_PLATFORM_MINGW32
 # if !defined(__MINGW32__) /* HOSTCC is called */
 #  undef ENABLE_PLATFORM_MINGW32
+# else
+#  undef __USE_MINGW_ANSI_STDIO
+#  define __USE_MINGW_ANSI_STDIO 0
+#  undef _WIN32_WINNT
+#  define _WIN32_WINNT 0x502
 # endif
 #else
 # if defined(__MINGW32__)
diff --git a/scripts/kconfig/mconf.c b/scripts/kconfig/mconf.c
index cda0473ac..d945f2cd5 100644
--- a/scripts/kconfig/mconf.c
+++ b/scripts/kconfig/mconf.c
@@ -31,9 +31,11 @@
 #include <unistd.h>
 #include <locale.h>
 
+#ifndef __MINGW32__
 #ifndef SIGWINCH
 #define SIGWINCH 28
 #endif
+#endif
 
 #define LKC_DIRECT_LINK
 #include "lkc.h"
diff --git a/win32/poll.c b/win32/poll.c
index 3294fdc96..8f16d93e9 100644
--- a/win32/poll.c
+++ b/win32/poll.c
@@ -23,6 +23,7 @@
 # pragma GCC diagnostic ignored "-Wtype-limits"
 #endif
 
+#include "libbb.h"
 #include <malloc.h>
 
 #include <sys/types.h>
@@ -37,9 +38,6 @@
 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
 # define WINDOWS_NATIVE
 # define WIN32_NATIVE
-# if defined (_MSC_VER)
-#  define _WIN32_WINNT 0x0502
-# endif
 # include <winsock2.h>
 # include <windows.h>
 # include <io.h>