Plugins: configure.ac: Be more helpful in absence of autoconf-archive…

… and/or pkg.m4

Suggested-by: Eli Schwartz <eschwartz93@gmail.com>

libvisual-plugins/configure.ac

@@ -32,6 +32,7 @@ fi
 
 dnl Check for libvisual here so that users get told they have the
 dnl wrong dependencies as early in the process as possible.
+m4_pattern_forbid([^PKG_CHECK_MODULES$])
 PKG_CHECK_MODULES([LIBVISUAL], [libvisual_pkg >= libvisual_required_version],
   [],
   [AC_MSG_ERROR([*** libvisual libvisual_required_version not found.
@@ -46,6 +47,7 @@ AC_PROG_CXX
 dnl Check for typedefs, structures, and compiler characteristics.
 AC_C_CONST
 AC_C_INLINE
+m4_pattern_forbid([^AX_CXX_COMPILE_STDCXX_11$])
 AX_CXX_COMPILE_STDCXX_11([noext], [mandatory])
 
 dnl 'Standard' header files.
@@ -100,6 +102,7 @@ AC_ARG_ENABLE([pulseaudio], AS_HELP_STRING([--disable-pulseaudio],
         [ENABLE_INPUT_PULSEAUDIO=$enableval],
 	[ENABLE_INPUT_PULSEAUDIO=yes])
 if test "$ENABLE_INPUT_PULSEAUDIO" = "yes"; then
+    m4_pattern_forbid([^PKG_CHECK_MODULES$])
     PKG_CHECK_MODULES([LIBPULSE], [libpulse], [HAVE_LIBPULSE="yes"], [HAVE_LIBPULSE="no"])
     if test "$HAVE_LIBPULSE" = "yes"; then
         build_input_plugins="$build_input_plugins pulseaudio"
@@ -116,6 +119,7 @@ AC_ARG_ENABLE([jack], AS_HELP_STRING([--disable-jack],
 	[ENABLE_INPUT_JACK=yes])
 
 if test "$ENABLE_INPUT_JACK" = "yes"; then
+m4_pattern_forbid([^PKG_CHECK_MODULES$])
 PKG_CHECK_MODULES([LIBJACK], [jack >= jack_required_version], [HAVE_JACK="yes"], [HAVE_JACK="no"])
 if test "$HAVE_JACK" = "yes"; then
   build_input_plugins="$build_input_plugins jack"
@@ -131,6 +135,7 @@ AC_ARG_ENABLE([portaudio], AS_HELP_STRING([--disable-portaudio],
         [ENABLE_INPUT_PORTAUDIO=$enableval],
 	[ENABLE_INPUT_PORTAUDIO=yes])
 AS_IF([test "$ENABLE_INPUT_PORTAUDIO" = yes], [
+    m4_pattern_forbid([^PKG_CHECK_MODULES$])
     PKG_CHECK_MODULES([PORTAUDIO], [portaudio-2.0], [HAVE_PORTAUDIO="yes"], [HAVE_PORTAUDIO="no"])
     AS_IF([test "$HAVE_PORTAUDIO" = yes], [
         build_input_plugins="$build_input_plugins portaudio"
@@ -148,6 +153,7 @@ AC_ARG_ENABLE([gdkpixbuf-plugin],
   [ENABLE_PLUGIN_GDKPIXBUF=yes])
 
 if test "$ENABLE_PLUGIN_GDKPIXBUF" = "yes"; then
+  m4_pattern_forbid([^PKG_CHECK_MODULES$])
   PKG_CHECK_MODULES([GTK], [gtk+-3.0 >= gtk_required_version],
     [HAVE_GTK="yes"], [HAVE_GTK="no"])
 
@@ -169,6 +175,7 @@ AC_ARG_ENABLE([gstreamer-plugin],
   [ENABLE_GSTREAMER_PLUGIN=yes])
 
 if test "$ENABLE_GSTREAMER_PLUGIN" = "yes"; then
+  m4_pattern_forbid([^PKG_CHECK_MODULES$])
   PKG_CHECK_MODULES([GSTREAMER], [gstreamer-1.0 >= gst_required_version],
     [HAVE_GSTREAMER="yes"], [HAVE_GSTREAMER="no"])
 
@@ -189,7 +196,9 @@ AC_ARG_ENABLE([opengl],
   [ENABLE_OPENGL_ACTORS=yes])
 
 AS_IF([test "$ENABLE_OPENGL_ACTORS" = "yes"], [
+  m4_pattern_forbid([^AX_CHECK_GL$])
   AX_CHECK_GL([HAVE_OPENGL="yes"], [HAVE_OPENGL="no"])
+  m4_pattern_forbid([^AX_CHECK_GLU$])
   AX_CHECK_GLU([HAVE_GLU="yes"], [HAVE_GLU="no"; HAVE_OPENGL="no"])
   AS_IF([test "$HAVE_OPENGL" != "yes"], [
     AC_MSG_WARN([*** OpenGL and/or GLU have not been found, see above.