diff --git a/lang/gauche/Makefile b/lang/gauche/Makefile
index 8ffa9a99d774..bf5b6d4d5039 100644
--- a/lang/gauche/Makefile
+++ b/lang/gauche/Makefile
@@ -19,7 +19,6 @@ BROKEN_armv6=	Fails to build: unknown attribute __alloc_size__; also fails in as
 BROKEN_armv7=	Fails to build: unknown attribute __alloc_size__; also fails in assembler
 BROKEN_mips=	Fails to build: redefinition of GC_register_dynamic_libraries
 BROKEN_mips64=	Fails to build: redefinition of GC_register_dynamic_libraries
-BROKEN_sparc64=	Fails to build: do not know how to make sparc_mach_dep.lo
 
 USES=		iconv makeinfo tar:tgz
 GNU_CONFIGURE=	yes
@@ -63,8 +62,9 @@ CONFIGURE_ARGS+=	--enable-multibyte=none
 .endif
 
 post-patch:
+# required for sparc64, no-op elsewhere
 	@${REINPLACE_CMD} -e \
-		's|-lpthread|-pthread|' ${WRKSRC}/configure
+		'/^VPATH = /s,$$,/src,' ${WRKSRC}/gc/Makefile.in
 
 post-install:
 	@${TOUCH} ${STAGEDIR}${PREFIX}/lib/gauche-0.9/site/${CONFIGURE_TARGET}/.keepme