--- configure.orig	2020-02-02 11:58:46 UTC
+++ configure
@@ -22138,7 +22138,7 @@ $as_echo_n "checking whether pthread_t is integer... "
 int
 main ()
 {
-pthread_t k; k * 1;
+pthread_t k; k = (pthread_t) -1;
   ;
   return 0;
 }
@@ -26130,7 +26130,7 @@ for be in ${BACKENDS}; do
     ;;
 
     v4l)
-    if test "${have_linux_ioctl_defines}" != "yes" \
+    if test "${have_libv4l1}" != "yes" \
       || test "${have_libv4l1}" != "yes"; then
       echo "*** $be backend requires v4l libraries - $DISABLE_MSG"
       backend_supported="no"
@@ -26339,7 +26339,7 @@ for be in ${BACKENDS}; do
     ;;
 
     v4l)
-    if test "${have_linux_ioctl_defines}" != "yes" \
+    if test "${have_libv4l1}" != "yes" \
       || test "${have_libv4l1}" != "yes"; then
       echo "*** $be backend requires v4l libraries - $DISABLE_MSG"
       backend_supported="no"