diff --git a/Makefile b/Makefile
index fc799bf9..105ff456 100644
--- a/Makefile
+++ b/Makefile
@@ -4,8 +4,6 @@ VERSION = 1.dev
 FLAGS += -DVERSION=$(VERSION)
 FLAGS += -Iinclude
 FLAGS += -Idep/include -Idep/lib/libzip/include
-FLAGS += -fopenmp
-LDFLAGS += -fopenmp
 
 include arch.mk
 
@@ -20,8 +18,7 @@ SOURCES += $(wildcard src/*.cpp src/*/*.cpp)
 
 ifdef ARCH_MAC
 	SOURCES += dep/osdialog/osdialog_mac.m
-	CXXFLAGS += -stdlib=libc++
-	LDFLAGS += -stdlib=libc++ -lpthread -ldl \
+	LDFLAGS += -lpthread -ldl \
 		-framework Cocoa -framework OpenGL -framework IOKit -framework CoreVideo -framework CoreAudio -framework CoreMIDI \
 		-Ldep/lib dep/lib/libglfw3.a dep/lib/libGLEW.a dep/lib/libjansson.a dep/lib/libspeexdsp.a dep/lib/libzip.a dep/lib/libz.a dep/lib/librtaudio.a dep/lib/librtmidi.a dep/lib/libcrypto.a dep/lib/libssl.a dep/lib/libcurl.a
 	TARGET := Rack
@@ -29,6 +26,8 @@ ifdef ARCH_MAC
 endif
 
 ifdef ARCH_WIN
+	FLAGS += -fopenmp
+	LDFLAGS += -fopenmp
 	SOURCES += dep/osdialog/osdialog_win.c
 	LDFLAGS += -static \
 		-Wl,--export-all-symbols,--out-implib,libRack.a -mwindows \
@@ -39,6 +38,8 @@ ifdef ARCH_WIN
 endif
 
 ifdef ARCH_LIN
+	FLAGS += -fopenmp
+	LDFLAGS += -fopenmp
 	SOURCES += dep/osdialog/osdialog_gtk2.c
 	CFLAGS += $(shell pkg-config --cflags gtk+-2.0)
 	LDFLAGS += -rdynamic \
diff --git a/dep.mk b/dep.mk
index d7c304fb..75c6c0bd 100644
--- a/dep.mk
+++ b/dep.mk
@@ -28,7 +28,11 @@ endif
 # Some platforms try to install to lib64
 CMAKE += -DCMAKE_INSTALL_LIBDIR=lib
 
-SHA256 := sha256check() { echo "$$2" "$$1" | sha256sum -c; }; sha256check
+ifdef ARCH_MAC
+	SHA256 := sha256check() { echo "$$2  $$1" | shasum -a 256 -c; }; sha256check
+else
+	SHA256 := sha256check() { echo "$$2  $$1" | sha256sum -c; }; sha256check
+endif
 
 # Export environment for all dependency targets
 $(DEPS): export CFLAGS = $(DEP_CFLAGS)
diff --git a/src/engine/Engine.cpp b/src/engine/Engine.cpp
index 6c0c05ce..7c9311de 100644
--- a/src/engine/Engine.cpp
+++ b/src/engine/Engine.cpp
@@ -8,7 +8,6 @@
 #include <thread>
 #include <condition_variable>
 #include <mutex>
-#include <omp.h>
 #include <xmmintrin.h>
 #include <pmmintrin.h>