diff --git a/GNUmakefile b/GNUmakefile
index 7d49eba3..41531fb3 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -79,6 +79,7 @@ CC := $(CC) -b glibc
 
 # getopt is in libc.
 GETOPT =
+GETOPT_SRC =
 
 CPPFLAGS := -DSTDC_HEADERS -DHAVE_UNISTD_H -DHAVE_GLOB_H \
 	    -DHAVE_GETDTABLESIZE -DHAVE_SYS_SIGLIST -DHAVE_DUP2 \