[libpng15] Updated scripts/makefile.* to use CPPFLAGS (Cosmin)

scripts/makefile.elf

@@ -54,8 +54,8 @@ WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 
 # for pgcc version 2.95.1, -O3 is buggy; don't use it.
 
-CFLAGS=-W -Wall -D_REENTRANT -O2 \
-	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
+CPPFLAGS=-D_REENTRANT # -DPNG_DEBUG=5
+CFLAGS=-W -Wall -O2 $(ALIGN) # $(WARNMORE) -g
 
 LDFLAGS=-L. -lpng15
 LDFLAGS_A=libpng.a -lz -lm
@@ -90,6 +90,9 @@ OBJSDLL = $(OBJS:.o=.pic.o)
 
 .SUFFIXES:      .c .o .pic.o
 
+.c.o:
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
+
 .c.pic.o:
 	$(CC) -c $(CFLAGS) -fPIC -o $@ $*.c
 
@@ -111,7 +114,7 @@ libpng.pc:
 	-e s!-lpng15!-lpng15\ -lz\ -lm! > libpng.pc
 
 libpng.syms: png.h pngconf.h pnglibconf.h
-	$(CC) $(CFLAGS) -E -DPNG_BUILDSYMS -DPNG_INTERNAL png.h |\
+	$(CC) $(CPPFLAGS) $(CFLAGS) -E -DPNG_BUILDSYMS -DPNG_INTERNAL png.h |\
 	awk -F '[\t [\\]();]' -v PNGMAJ=$(PNGMAJ) 'BEGIN{printf("PNG15_%s {global:\n",PNGMAJ)}\
 	{ for (i=1;i+2<=NF;++i)\
 		if ($$(i)=="PNG_FUNCTION_EXPORT" && $$(i+2)=="END")\
@@ -220,14 +223,14 @@ install: install-static install-shared install-man install-config
 test-dd:
 	echo
 	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) -I$(ZLIBINC) \
+	$(CC) -I$(DI) $(CPPFLAGS) \
 	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
 	   -L$(DL) -L$(ZLIBLIB) -Wl, -rpath,$(DL) -Wl,-rpath,$(ZLIBLIB) \
 	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
 	./pngtestd pngtest.png
 
 test-installed:
-	$(CC) -I$(ZLIBINC) \
+	$(CC) $(CPPFLAGS) \
 	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
 	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
 	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`