No fpic on Windows C++. Closes #690.

mesonbuild/compilers.py

@@ -1869,6 +1869,11 @@ class GnuCPPCompiler(CPPCompiler):
             return gnu_color_args[colortype][:]
         return []
 
+    def get_pic_args(self):
+        if self.gcc_type == GCC_MINGW:
+            return [] # On Window gcc defaults to fpic being always on.
+        return ['-fPIC']
+
     def get_always_args(self):
         return ['-pipe']