diff --git a/AVRsack.xcodeproj/project.pbxproj b/AVRsack.xcodeproj/project.pbxproj
index 42e5e2f..5722dc4 100644
--- a/AVRsack.xcodeproj/project.pbxproj
+++ b/AVRsack.xcodeproj/project.pbxproj
@@ -539,7 +539,7 @@
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				MTL_ENABLE_DEBUG_INFO = YES;
 				ONLY_ACTIVE_ARCH = YES;
-				SDKROOT = macosx;
+				SDKROOT = macosx10.12;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 			};
 			name = Debug;
@@ -577,7 +577,7 @@
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				MTL_ENABLE_DEBUG_INFO = NO;
-				SDKROOT = macosx;
+				SDKROOT = macosx10.12;
 			};
 			name = Release;
 		};