Skip building sk-dummy library if no SK support.
diff --git a/Makefile.in b/Makefile.in
index 7c5ed0b..c9e4294 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -635,6 +635,8 @@
regress/misc/sk-dummy/fatal.lo \
ed25519.lo hash.lo ge25519.lo fe25519.lo sc25519.lo verify.lo
+SK_DUMMY_LIBRARY=@SK_DUMMY_LIBRARY@
+
.c.lo: Makefile.in config.h
$(CC) $(CFLAGS_NOPIE) $(PICFLAG) $(CPPFLAGS) -c $< -o $@
@@ -648,7 +650,7 @@
regress/netcat$(EXEEXT) \
regress/check-perm$(EXEEXT) \
regress/mkdtemp$(EXEEXT) \
- regress/misc/sk-dummy/sk-dummy.so
+ $(SK_DUMMY_LIBRARY)
regress-unit-binaries: regress-prep $(REGRESSLIBS) \
regress/unittests/sshbuf/test_sshbuf$(EXEEXT) \
diff --git a/configure.ac b/configure.ac
index 003b235..4603837 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3137,6 +3137,10 @@
AC_MSG_CHECKING([whether to enable U2F])
if test "x$enable_sk" = "xyes" ; then
AC_DEFINE([ENABLE_SK], [], [Enable for U2F/FIDO support])
+ AC_SUBST(SK_DUMMY_LIBRARY, [regress/misc/sk-dummy/sk-dummy.so])
+else
+ # Do not try to build sk-dummy library.
+ AC_SUBST(SK_DUMMY_LIBRARY, [""])
fi
AC_MSG_RESULT([$enable_sk])