fix for macos and windows compiler tool chains

my silly linker options are not appreciated on those platforms, it's
sufficient to test this on linux only as there is nothing really platfrom
specific about this code.

tests/vm/tcompilesetting.nim

@@ -13,7 +13,8 @@ template main =
   doAssert querySetting(backend) == "c"
   doAssert fileExists(libPath.querySetting / "system.nim")
   doAssert "-fmax-errors=4" in querySetting(compileOptions)
-  doAssert "-u dummysymboldoesnotexist" in querySetting(linkOptions), querySetting(linkOptions)
+  when not defined(macos) and not defined(windows):
+    doAssert "-u dummysymboldoesnotexist" in querySetting(linkOptions)
 
 static: main()
 main()