MinGW compilation fixes.

dmd2/mars.h

@@ -365,7 +365,7 @@ extern Global global;
 /* Set if Windows Structured Exception Handling C extensions are supported.
  * Apparently, VC has dropped support for these?
  */
-#define WINDOWS_SEH     _WIN32
+#define WINDOWS_SEH     (_WIN32 && !defined(__MINGW32__))
 
 #include "longdouble.h"
 

dmd2/root/response.c

@@ -29,7 +29,7 @@
 #include <utime.h>
 #endif
 
-#if _MSC_VER
+#if _MSC_VER || defined(__MINGW32__)
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <fcntl.h>

dmd2/root/speller.c

@@ -14,6 +14,8 @@
 
 #if __sun || _MSC_VER
 #include <alloca.h>
+#elif __MINGW32__
+#include <malloc.h>
 #endif
 
 #include "speller.h"

driver/linker.cpp

@@ -411,7 +411,7 @@ int runExecutable()
     int status = executeToolAndWait(gExePath, opts::runargs, global.params.verbose);
     if (status < 0)
     {
-#if defined(_MSC_VER)
+#if defined(_MSC_VER) || defined(__MINGW32__)
         error("program received signal %d", -status);
 #else
         error("program received signal %d (%s)", -status, strsignal(-status));