diff --git a/Makefile.am b/Makefile.am
index 140f95bfb2..1401d7dda0 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -429,6 +429,7 @@ wireshark_LDADD = \
 	ui/qt/libqtui.a \
 	$(wireshark_common_ldadd) \
 	@Qt_LIBS@
+wireshark_CPPFLAGS = $(AM_CPPFLAGS) $(Qt_CFLAGS)
 endif
 
 if HAVE_GTK
diff --git a/acinclude.m4 b/acinclude.m4
index 38555a03fc..14a848883c 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -2104,8 +2104,6 @@ AC_DEFUN([AC_WIRESHARK_QT_CHECK],
 
 		AC_WIRESHARK_QT_ADD_PIC_IF_NEEDED
 
-		AC_SUBST(Qt_LIBS)
-
 		# Run Action-If-Found
 		ifelse([$3], , :, [$3])
 	else
diff --git a/configure.ac b/configure.ac
index 1ab3d29c4d..e170fb03b7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1644,8 +1644,8 @@ if test "x$enable_wireshark" = "xyes"; then
 		#
 		AC_WIRESHARK_QT_CHECK($QT_MIN_VERSION, "$with_qt",
 		[
-			WS_CFLAGS="$WS_CFLAGS $Qt_CFLAGS"
-			WS_CXXFLAGS="$WS_CXXFLAGS $Qt_CFLAGS"
+			AC_SUBST(Qt_CFLAGS)
+			AC_SUBST(Qt_LIBS)
 			have_qt=yes
 			GUI_CONFIGURE_FLAGS="$GUI_CONFIGURE_FLAGS --with-qt"
 
diff --git a/ui/qt/Makefile.am b/ui/qt/Makefile.am
index f276a9663f..bf9f8c82e5 100644
--- a/ui/qt/Makefile.am
+++ b/ui/qt/Makefile.am
@@ -22,7 +22,7 @@
 include Makefile.common
 include $(top_srcdir)/Makefile.am.inc
 
-AM_CPPFLAGS += $(LIBGCRYPT_CFLAGS) $(LIBGNUTLS_CFLAGS)
+AM_CPPFLAGS += $(LIBGCRYPT_CFLAGS) $(LIBGNUTLS_CFLAGS) $(Qt_CFLAGS)
 
 noinst_LIBRARIES = libqtui.a