Merge pull request #1191 from geoffw0/microsoft

CPP: Workaround improvement for File.compiledAsMicrosoft.

cpp/ql/src/semmle/code/cpp/File.qll

@@ -309,6 +309,12 @@ class File extends Container, @file {
     ) or exists(File parent |
       parent.compiledAsMicrosoft() and
       parent.getAnIncludedFile() = this
+    ) or (
+      getAbsolutePath().charAt(1) = ":"
+      	// this is not ideal, it detects compilation on a Windows file system
+      	// as a heuristic approximation to compilation with a Microsoft compiler.
+    ) or (
+      getAbsolutePath().charAt(1) = "/"
     )
   }