sparc64 (and presumably other ld.bfd arches) need "-L${X11BASE}/lib" added to the LDFLAGS for the build to complete sucessfully.
ok? --Kurt Index: Makefile =================================================================== RCS file: /cvs/ports/games/stone-soup/Makefile,v retrieving revision 1.38 diff -u -p -r1.38 Makefile --- Makefile 12 Jul 2019 21:42:15 -0000 1.38 +++ Makefile 25 Apr 2020 22:27:34 -0000 @@ -59,7 +59,8 @@ CFLAGS += -DUSE_TILE CXXFLAGS += -DUSE_TILE MAKE_FLAGS += TILES=y \ - LDFLAGS="-L${LOCALBASE}/lib -lSDL2 -lSDL2_image -lpng -pthread" + LDFLAGS="-L${LOCALBASE}/lib -L${X11BASE}/lib \ + -lSDL2 -lSDL2_image -lpng -pthread" WANTLIB += GL GLU SDL2 SDL2_image freetype png pthread z RUN_DEPENDS = devel/desktop-file-utils LIB_DEPENDS += devel/sdl2 \