Index: noto-emoji-e7a7241a929625feb16920a40bfa29e4a302b82b/Makefile
===================================================================
--- noto-emoji-e7a7241a929625feb16920a40bfa29e4a302b82b.orig/Makefile
+++ noto-emoji-e7a7241a929625feb16920a40bfa29e4a302b82b/Makefile
@@ -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 = `pkg-config --libs cairo`
-PNGQUANTDIR := third_party/pngquant
-PNGQUANT := $(PNGQUANTDIR)/pngquant
+PNGQUANT = pngquant
 PNGQUANTFLAGS = --speed 1 --skip-if-larger --force
 
 # zopflipng is better (about 5-10%) but much slower.  it will be used if
@@ -92,6 +91,12 @@ ALL_QUANTIZED_FILES = $(addprefix $(QUAN
 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
@@ -121,6 +126,11 @@ quantized: $(ALL_QUANTIZED_FILES)
 
 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
@@ -141,8 +151,7 @@ endif
 $(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)
@@ -213,5 +222,5 @@ clean:
 .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