diff --git a/.gitignore b/.gitignore
index 567609b12..4df07c20b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 build/
+build-release/
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5354d2eac..8bdb7ad7c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,7 +1,9 @@
-cmake_minimum_required(VERSION 2.8)
+cmake_minimum_required(VERSION 2.8.5)
 
-set(CMAKE_BUILD_TYPE "Debug" CACHE STRING
-    "Choose the type of build, options are: Debug Release RelWithDebInfo MinSizeRel." FORCE)
+if(NOT CMAKE_BUILD_TYPE)
+    set(CMAKE_BUILD_TYPE "Debug" CACHE STRING
+        "Choose the type of build, options are: Debug Release RelWithDebInfo MinSizeRel." FORCE)
+endif()
 
 project(zig CXX)
 set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake ${CMAKE_MODULE_PATH})
@@ -142,9 +144,9 @@ include_directories(
     "${CMAKE_SOURCE_DIR}/src"
 )
 
-set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} -Wno-unused-variable -Wno-unused-but-set-variable")
+set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -Werror -Wall -pedantic")
 
-set(EXE_CFLAGS "-std=c++11 -fno-exceptions -fno-rtti -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Werror -Wall -Werror=strict-prototypes -Werror=old-style-definition -Werror=missing-prototypes")
+set(EXE_CFLAGS "-std=c++11 -fno-exceptions -fno-rtti -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Werror=strict-prototypes -Werror=old-style-definition -Werror=missing-prototypes")
 
 add_executable(zig ${ZIG_SOURCES})
 set_target_properties(zig PROPERTIES