add devel subpackages, my sample application compiles fine

package/sdl-image/Makefile

@@ -20,6 +20,11 @@ WRKDIST=		${WRKDIR}/SDL_image-${PKG_VERSION}
 include $(TOPDIR)/mk/package.mk
 
 $(eval $(call PKG_template,LIBSDL_IMAGE,libsdl-image,$(PKG_VERSION)-${PKG_RELEASE},${PKG_DEPENDS},${PKG_DESCR},${PKG_SECTION}))
+$(eval $(call PKG_template,LIBSDL_IMAGE_DEV,libsdl-image-dev,$(PKG_VERSION)-${PKG_RELEASE},libsdl-image,${PKG_DESCR},${PKG_SECTION}))
+
+SUB_INSTALLS-y:=
+SUB_INSTALLS-m:=
+SUB_INSTALLS-${ADK_PACKAGE_LIBSDL_IMAGE_DEV}+=	libsdl-image-dev-install
 
 CONFIGURE_STYLE:=	gnu
 CONFIGURE_ARGS+=	--enable-png \
@@ -29,8 +34,13 @@ CONFIGURE_ARGS+=	--enable-png \
 BUILD_STYLE:=		auto
 INSTALL_STYLE:=		auto
 
-post-install:
+post-install: ${SUB_INSTALLS-m} ${SUB_INSTALLS-y}
 	$(INSTALL_DIR) $(IDIR_LIBSDL_IMAGE)/usr/lib
 	$(CP) ${WRKINST}/usr/lib/libSDL*.so* $(IDIR_LIBSDL_IMAGE)/usr/lib
 
+libsdl-image-dev-install:
+	$(INSTALL_DIR) $(IDIR_LIBSDL_IMAGE_DEV)/usr/include/SDL
+	$(CP) ${WRKINST}/usr/include/SDL/*.h \
+		$(IDIR_LIBSDL_IMAGE_DEV)/usr/include/SDL
+
 include ${TOPDIR}/mk/pkg-bottom.mk

package/sdl/Makefile

@@ -20,6 +20,11 @@ WRKDIST=		${WRKDIR}/SDL-${PKG_VERSION}
 include $(TOPDIR)/mk/package.mk
 
 $(eval $(call PKG_template,LIBSDL,libsdl,$(PKG_VERSION)-${PKG_RELEASE},${PKG_DEPENDS},${PKG_DESCR},${PKG_SECTION}))
+$(eval $(call PKG_template,LIBSDL_DEV,libsdl-dev,$(PKG_VERSION)-${PKG_RELEASE},libsdl,${PKG_DESCR},${PKG_SECTION}))
+
+SUB_INSTALLS-y:=
+SUB_INSTALLS-m:=
+SUB_INSTALLS-${ADK_PACKAGE_LIBSDL_DEV}+=	libsdl-dev-install
 
 CONFIGURE_STYLE:=	gnu
 CONFIGURE_ARGS+=	--disable-esd \
@@ -33,8 +38,12 @@ CONFIGURE_ARGS+=	--disable-esd \
 BUILD_STYLE:=		auto
 INSTALL_STYLE:=		auto
 
-post-install:
+post-install: ${SUB_INSTALLS-m} ${SUB_INSTALLS-y}
 	$(INSTALL_DIR) $(IDIR_LIBSDL)/usr/lib
 	$(CP) ${WRKINST}/usr/lib/libSDL*.so* $(IDIR_LIBSDL)/usr/lib
 
+libsdl-dev-install:
+	$(INSTALL_DIR) $(IDIR_LIBSDL_DEV)/usr/include/SDL
+	$(CP) ${WRKINST}/usr/include/SDL/* $(IDIR_LIBSDL_DEV)/usr/include/SDL
+
 include ${TOPDIR}/mk/pkg-bottom.mk