qt tools are optional

ChangeLog

@@ -1,3 +1,13 @@
+2015-03-04 13:28  marc
+
+	* m4/ax_check_qt.m4: try to fix «HAVE_QTNETWORK does not appear in
+	  AM_CONDITIONAL» when there is no qt
+
+2015-03-03 18:37  marc
+
+	* ChangeLog, README, configure.ac, debian/control.in: now also
+	  depends on qt
+
 2015-03-03 15:56  marc
 
 	* AUTHORS, ChangeLog, configure.ac, debian/changelog.in,

m4/ax_check_qt.m4

@@ -27,6 +27,9 @@
 #      data files themselves.
 
 AC_DEFUN([AX_CXX_QT_TOOL], [
+  if test -z "$HAVE_$1"; then
+    HAVE_$1=1
+    AC_MSG_CHECKING([for $2])
     AC_ARG_VAR([$1], [path to Qt tool $2])
     $1=${$1:-$(pkg-config --variable=$2_location Qt5Core)}
     $1=${$1:-$(pkg-config --variable=host_bins Qt5Core)/$2}
@@ -36,15 +39,18 @@ AC_DEFUN([AX_CXX_QT_TOOL], [
       if which "$2" > /dev/null; then
         $1=$2
       else
-      if test -n "$$1"; then
-        AC_MSG_ERROR([Missing Qt program: $2 (tested: $$1)])
-      else
-        AC_MSG_ERROR([Missing Qt program: $2 (specify variable $1)])
-      fi
+        HAVE_$1=0
+        $1=""
       fi
     fi
     AC_SUBST($1)
-  AC_MSG_NOTICE([using $$1 for $2])
+    AM_CONDITIONAL(HAVE_$1, test $HAVE_$1 -eq 1)
+    if test $HAVE_$1 -eq 1; then
+      AC_MSG_RESULT([$$1])
+    else
+      AC_MSG_RESULT([not found])
+    fi
+  fi
 ])
 
 AC_DEFUN([AX_CXX_QT_TOOLS], [