diff --git a/compat.c b/compat.c
index 26037b95..fb35b09e 100644
--- a/compat.c
+++ b/compat.c
@@ -42,9 +42,8 @@ time_t openconnect__time(time_t *t)
 }
 #endif
 
-#ifndef HAVE_ASPRINTF
-
-static int oc_vasprintf(char **strp, const char *fmt, va_list ap)
+#ifndef HAVE_VASPRINTF
+int openconnect__vasprintf(char **strp, const char *fmt, va_list ap)
 {
 	va_list ap2;
 	char *res = NULL;
@@ -102,14 +101,16 @@ static int oc_vasprintf(char **strp, const char *fmt, va_list ap)
 	*strp = res;
 	return ret;
 }
+#endif
 
+#ifndef HAVE_ASPRINTF
 int openconnect__asprintf(char **strp, const char *fmt, ...)
 {
 	va_list ap;
 	int ret;
 
 	va_start(ap, fmt);
-	ret = oc_vasprintf(strp, fmt, ap);
+	ret = vasprintf(strp, fmt, ap);
 	va_end(ap);
 	return ret;
 }
diff --git a/configure.ac b/configure.ac
index a0b857f1..4456bdee 100644
--- a/configure.ac
+++ b/configure.ac
@@ -23,6 +23,8 @@ m4_ifdef([PKG_INSTALLDIR], [PKG_INSTALLDIR],
 use_openbsd_libtool=
 symver_time=
 symver_getline=
+symver_asprintf=
+symver_vasprintf=
 
 case $host_os in
  *linux* | *gnu*)
@@ -106,8 +108,12 @@ AC_CHECK_FUNC(getline, [AC_DEFINE(HAVE_GETLINE, 1, [Have getline() function])],
     [symver_getline="openconnect__getline;"])
 AC_CHECK_FUNC(strcasestr, [AC_DEFINE(HAVE_STRCASESTR, 1, [Have strcasestr() function])], [])
 AC_CHECK_FUNC(strndup, [AC_DEFINE(HAVE_STRNDUP, 1, [Have strndup() function])], [])
-AC_CHECK_FUNC(asprintf, [AC_DEFINE(HAVE_ASPRINTF, 1, [Have asprintf() function])], [])
-if test -n "$symver_asprintf"; then
+AC_CHECK_FUNC(asprintf, [AC_DEFINE(HAVE_ASPRINTF, 1, [Have asprintf() function])],
+    [symver_asprintf="openconnect__asprintf;"])
+AC_CHECK_FUNC(vasprintf, [AC_DEFINE(HAVE_VASPRINTF, 1, [Have vasprintf() function])],
+    [symver_vasprintf="openconnect__vasprintf;"])
+
+if test -n "$symver_vasprintf"; then
   AC_MSG_CHECKING([for va_copy])
   AC_LINK_IFELSE([AC_LANG_PROGRAM([
 	#include <stdarg.h>
@@ -126,11 +132,13 @@ if test -n "$symver_asprintf"; then
 		[AC_DEFINE(HAVE___VA_COPY, 1, [Have __va_copy()])
 		AC_MSG_RESULT(__va_copy)],
 		[AC_MSG_RESULT(no)
-		AC_MSG_ERROR([Your system lacks asprintf() and va_copy()])])
+		AC_MSG_ERROR([Your system lacks vasprintf() and va_copy()])])
 	])
 fi
 AC_SUBST(SYMVER_TIME, $symver_time)
 AC_SUBST(SYMVER_GETLINE, $symver_getline)
+AC_SUBST(SYMVER_ASPRINTF, $symver_asprintf)
+AC_SUBST(SYMVER_VASPRINTF, $symver_vasprintf)
 
 AS_COMPILER_FLAGS(WFLAGS,
         "-Wall
diff --git a/libopenconnect.map.in b/libopenconnect.map.in
index 1a8675af..1774ac1f 100644
--- a/libopenconnect.map.in
+++ b/libopenconnect.map.in
@@ -62,7 +62,7 @@ OPENCONNECT_3.3 {
 } OPENCONNECT_3.1;
 
 OPENCONNECT_PRIVATE {
- global: @SYMVER_TIME@ @SYMVER_GETLINE@ @SYMVER_JAVA@
+ global: @SYMVER_TIME@ @SYMVER_GETLINE@ @SYMVER_JAVA@ @SYMVER_ASPRINTF@ @SYMVER_VASPRINTF@
 	openconnect_version_str;
 	openconnect_sha1;
  local:
diff --git a/openconnect-internal.h b/openconnect-internal.h
index d35c361a..8a9c9262 100644
--- a/openconnect-internal.h
+++ b/openconnect-internal.h
@@ -445,6 +445,10 @@ struct openconnect_info {
 #define time(x) openconnect__time(x)
 time_t openconnect__time(time_t *t);
 #endif
+#ifndef HAVE_VASPRINTF
+#define vasprintf openconnect__vasprintf
+int openconnect__vasprintf(char **strp, const char *fmt, va_list ap);
+#endif
 #ifndef HAVE_ASPRINTF
 #define asprintf openconnect__asprintf
 int openconnect__asprintf(char **strp, const char *fmt, ...);