build: quit creating a.out

redirect gcc to /dev/null to avoid writing to a file

diff --git a/configure.in b/configure.in
index 7c2149f..763b7ee 100755 (executable)
--- a/configure.in
+++ b/configure.in
@@ -20,7 +20,7 @@ AC_DEFUN([XB_FIND_SONAME],
 [
   if [[ "$host_vendor" != "apple" ]]; then
     AC_MSG_CHECKING([for lib$2 soname])
-    $1_FILENAME=$($CC -nostdlib $LDFLAGS -l$2 -Wl,-M 2>/dev/null | grep "^LOAD.*$2" | awk '{V=2; print $V}')
+    $1_FILENAME=$($CC -nostdlib -o /dev/null $LDFLAGS -l$2 -Wl,-M 2>/dev/null | grep "^LOAD.*$2" | awk '{V=2; print $V}')
     if [[ ! -z $$1_FILENAME ]]; then
       $1_SONAME=$(objdump -p $$1_FILENAME | grep "SONAME.*$2" | awk '{V=2; print $V}')
     fi