diff -ru noto-emoji-ff566b2c16f9332dc54e1b538e2bce2d213c0e3d.orig/Makefile noto-emoji-ff566b2c16f9332dc54e1b538e2bce2d213c0e3d/Makefile
--- noto-emoji-ff566b2c16f9332dc54e1b538e2bce2d213c0e3d.orig/Makefile	2017-04-25 22:02:45.000000000 +0200
+++ noto-emoji-ff566b2c16f9332dc54e1b538e2bce2d213c0e3d/Makefile	2017-04-26 09:55:23.736788590 +0200
@@ -15,10 +15,9 @@
 EMOJI = NotoColorEmoji
 font: $(EMOJI).ttf
 
-CFLAGS = -std=c99 -Wall -Wextra `pkg-config --cflags --libs cairo`
+CFLAGS = $(OPT_CFLAGS) `pkg-config --cflags --libs cairo`
 LDFLAGS = -lm `pkg-config --libs cairo`
-PNGQUANTDIR := third_party/pngquant
-PNGQUANT := $(PNGQUANTDIR)/pngquant
+PNGQUANT = pngquant
 PNGQUANTFLAGS = --speed 1 --skip-if-larger --quality 85-95 --force
 IMOPS = -size 136x128 canvas:none -compose copy -gravity center
 
@@ -96,6 +95,12 @@
 ALL_COMPRESSED_FILES = $(addprefix $(COMPRESSED_DIR)/, $(ALL_NAMES))
 
 # tool checks
+ifeq (,$(shell which $(PNGQUANT)))
+  ifeq (,$(wildcard $(PNGQUANT)))
+    MISSING_PNGQUANT = fail
+  endif
+endif
+
 ifeq (,$(shell which $(ZOPFLIPNG)))
   ifeq (,$(wildcard $(ZOPFLIPNG)))
     MISSING_ZOPFLI = fail
@@ -125,6 +130,11 @@
 
 compressed: $(ALL_COMPRESSED_FILES)
 
+check_quantization_tool:
+ifdef MISSING_PNGQUANT
+	$(error "$(PNGQUANT) is not available")
+endif
+
 check_compress_tool:
 ifdef MISSING_ZOPFLI
   ifdef MISSING_OPTIPNG
@@ -145,8 +155,7 @@
 $(EMOJI_DIR) $(FLAGS_DIR) $(RESIZED_FLAGS_DIR) $(RENAMED_FLAGS_DIR) $(QUANTIZED_DIR) $(COMPRESSED_DIR):
 	mkdir -p "$@"
 
-$(PNGQUANT):
-	$(MAKE) -C $(PNGQUANTDIR)
+$(PNGQUANT): check_quantization_tool
 
 waveflag: waveflag.c
 	$(CC) $< -o $@ $(CFLAGS) $(LDFLAGS)
@@ -226,5 +235,5 @@
 .SECONDARY: $(EMOJI_FILES) $(FLAG_FILES) $(RESIZED_FLAG_FILES) $(RENAMED_FLAG_FILES) \
   $(ALL_QUANTIZED_FILES) $(ALL_COMPRESSED_FILES)
 
-.PHONY:	clean flags emoji renamed_flags quantized compressed check_compress_tool
+.PHONY:	clean flags emoji renamed_flags quantized compressed check_compress_tool check_quantization_tool