From 3de98f7a9de348c00c39b31e8fb8d7ecc0ef5f36 Mon Sep 17 00:00:00 2001
From: Dennis Luxen <info@project-osrm.org>
Date: Mon, 14 Jul 2014 16:21:16 +0200
Subject: [PATCH] prevent in-source builds

---
 CMakeLists.txt | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 36556911c..f1293ba33 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,11 @@
 cmake_minimum_required(VERSION 2.8)
+
+if( CMAKE_SOURCE_DIR STREQUAL CMAKE_BINARY_DIR AND NOT MSVC_IDE )
+  message(FATAL_ERROR "In-source builds are not allowed.
+Please create a directory and run cmake from there, passing the path to this source directory as the last argument.
+This process created the file `CMakeCache.txt' and the directory `CMakeFiles'. Please delete them.")
+endif()
+
 project(OSRM)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 include(CheckCXXCompilerFlag)