diff --git a/ax_check_qt.m4 b/ax_check_qt.m4
index 26d9b4e..a2019a5 100644
--- a/ax_check_qt.m4
+++ b/ax_check_qt.m4
@@ -62,10 +62,16 @@ AC_DEFUN([AX_CXX_CHECK_QT], [
   PKG_CHECK_MODULES([$1], [${qt_modules//Qt/Qt5}], [
     HAVE_$1=1
     AC_DEFINE([HAVE_$1])
+    CPPFLAGS+=" ${$1_CFLAGS}"
+    CXXFLAGS+=" ${$1_CFLAGS}"
+    LIBS+=" ${$1_LIBS}"
   ], [
     PKG_CHECK_MODULES([$1], [${qt_modules}], [
       HAVE_$1=1
       AC_DEFINE([HAVE_$1])
+      CPPFLAGS+=" ${$1_CFLAGS}"
+      CXXFLAGS+=" ${$1_CFLAGS}"
+      LIBS+=" ${$1_LIBS}"
     ])
   ])
   AM_CONDITIONAL(HAVE_$1, test $HAVE_$1 -eq 1)