diff --git a/appveyor.yml b/appveyor.yml
index 81f27df45d5b5317d9a28a54544c397509d312fa..f7af702729ff5b0a80bddc0f9cfe1ff54dd50758 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -29,7 +29,7 @@ install:
 #- ps: (Get-Content [System.Environment]::ExpandEnvironmentVariables("%TMP%\%SDL2_MOVE%\lib\pkgconfig\sdl2.pc"))            | ForEach-Object { $_ -replace "/usr/local/cross-tools/i686-w64-mingw32", [System.Environment]::ExpandEnvironmentVariables("%MINGW_SDK%") } | Set-Content [System.Environment]::ExpandEnvironmentVariables("%MINGW_SDK%\lib\pkgconfig\sdl2.pc")
 
 before_build:
-- set CPPFLAGS=-I%TMP%\%SDL2_MOVE%\include\SDL2 -I%TMP%\%SDL2_MIXER_MOVE%\include\SDL2
+- set DEPFLAGS=-I%TMP%\%SDL2_MOVE%\include\SDL2 -I%TMP%\%SDL2_MIXER_MOVE%\include\SDL2
 - set SDL_CFLAGS=-I%TMP%\%SDL2_MOVE%\include\SDL2 -Dmain=SDL_main -I%TMP%\%SDL2_MIXER_MOVE%\include\SDL2
 - set SDL_LDFLAGS=-L%TMP%\%SDL2_MOVE%\lib  -lmingw32 -lSDL2main -lSDL2  -mwindows -L%TMP%\%SDL2_MIXER_MOVE%\lib
 - set Path=%MINGW_SDK%\bin;%Path%
diff --git a/src/Makefile b/src/Makefile
index 8474a7e875a9aa99ac504479ace17811f3ea2ce0..2c1de64d5ee049bb6b79c561bc1d76f072d158cf 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -703,13 +703,13 @@ $(OBJDIR)/depend.dep:
 	@echo "Creating dependency file, depend.dep"
 	@echo > comptime.h
 	-$(MKDIR) $(OBJDIR)
-	$(CC) $(CPPFLAGS) $(CFLAGS) -MM *.c > $(OBJDIR)/depend.ped
-	$(CC) $(CPPFLAGS) $(CFLAGS) -MM $(INTERFACE)/*.c >> $(OBJDIR)/depend.ped
+	$(CC) $(DEPFLAGS) $(CFLAGS) -MM *.c > $(OBJDIR)/depend.ped
+	$(CC) $(DEPFLAGS) $(CFLAGS) -MM $(INTERFACE)/*.c >> $(OBJDIR)/depend.ped
 ifndef NOHW
-	$(CC) $(CPPFLAGS) $(CFLAGS) -MM hardware/*.c >> $(OBJDIR)/depend.ped
+	$(CC) $(DEPFLAGS) $(CFLAGS) -MM hardware/*.c >> $(OBJDIR)/depend.ped
 endif
 ifndef NO_LUA
-	$(CC) $(CPPFLAGS) $(CFLAGS) -MM blua/*.c >> $(OBJDIR)/depend.ped
+	$(CC) $(DEPFLAGS) $(CFLAGS) -MM blua/*.c >> $(OBJDIR)/depend.ped
 endif
 	@sed -e 's,\(.*\)\.o: ,$(subst /,\/,$(OBJDIR))\/&,g' < $(OBJDIR)/depend.ped > $(OBJDIR)/depend.dep
 	$(REMOVE) $(OBJDIR)/depend.ped