Look for USERPROFILE and the combination of HOMEDRIVE and HOMEPATH to

get user's home directory in MinGW32 build.

Usually HOME environment variable is defined in *nix like OSes, but
not in Windows. So in MinGW32 build, if HOME is not defined, we also
look for USERPROFILE and the combination of HOMEDRIVE and HOMEPATH.

src/util.cc

@@ -986,6 +986,22 @@ std::string getHomeDir()
   if(p) {
     return p;
   } else {
+#ifdef __MINGW32__
+    p = getenv("USERPROFILE");
+    if(p) {
+      return p;
+    } else {
+      p = getenv("HOMEDRIVE");
+      if(p) {
+        std::string homeDir = p;
+        p = getenv("HOMEPATH");
+        if(p) {
+          homeDir += p;
+          return homeDir;
+        }
+      }
+    }
+#endif
     return A2STR::NIL;
   }
 }