Adds system expat library to link

Adds system zlib library to link when using local libid3tag
Fixes portmixer build when using local portaudio

configure

@@ -6337,6 +6337,7 @@ fi
       LIBID3TAG_LOCAL_LIBS="libid3tag.a"
       LIBID3TAG_LOCAL_CXXFLAGS='-I$(top_srcdir)/lib-src/libid3tag'
       LIBID3TAG_LOCAL_CPPSYMBOLS="USE_LIBID3TAG"
+      LIBS="${LIBS} -lz"
       { $as_echo "$as_me:${as_lineno-$LINENO}: libid3tag libraries are available in the local tree" >&5
 $as_echo "$as_me: libid3tag libraries are available in the local tree" >&6;}
    else
@@ -8193,7 +8194,7 @@ fi
       PORTAUDIO_LOCAL_LIBS="libportaudio.a"
       PORTAUDIO_LOCAL_CXXFLAGS='-I$(top_srcdir)/lib-src/portaudio-v19/include'
 
-            PORTAUDIO_LOCAL_CONFIGURE_ARGS="--with-pa-include=../portaudio-v19/include"
+            PORTAUDIO_LOCAL_CONFIGURE_ARGS="--with-pa-include=$(pwd)/lib-src/portaudio-v19/include"
 
       { $as_echo "$as_me:${as_lineno-$LINENO}: portaudio19 library is available in the local tree" >&5
 $as_echo "$as_me: portaudio19 library is available in the local tree" >&6;}
@@ -8911,6 +8912,66 @@ fi
          as_fn_error required by Audacity "dlopen not found" "$LINENO" 5
       fi
 
+      { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing XML_ParserCreate" >&5
+$as_echo_n "checking for library containing XML_ParserCreate... " >&6; }
+if ${ac_cv_search_XML_ParserCreate+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_func_search_save_LIBS=$LIBS
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char XML_ParserCreate ();
+int
+main ()
+{
+return XML_ParserCreate ();
+  ;
+  return 0;
+}
+_ACEOF
+for ac_lib in '' expat; do
+  if test -z "$ac_lib"; then
+    ac_res="none required"
+  else
+    ac_res=-l$ac_lib
+    LIBS="-l$ac_lib  $ac_func_search_save_LIBS"
+  fi
+  if ac_fn_cxx_try_link "$LINENO"; then :
+  ac_cv_search_XML_ParserCreate=$ac_res
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext
+  if ${ac_cv_search_XML_ParserCreate+:} false; then :
+  break
+fi
+done
+if ${ac_cv_search_XML_ParserCreate+:} false; then :
+
+else
+  ac_cv_search_XML_ParserCreate=no
+fi
+rm conftest.$ac_ext
+LIBS=$ac_func_search_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_XML_ParserCreate" >&5
+$as_echo "$ac_cv_search_XML_ParserCreate" >&6; }
+ac_res=$ac_cv_search_XML_ParserCreate
+if test "$ac_res" != no; then :
+  test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
+
+fi
+
+      if [ "$ac_cv_search_expat" = no ]; then
+         as_fn_error required by Audacity "expat not found" "$LINENO" 5
+      fi
+
 
 
 pkg_failed=no

configure.ac

@@ -596,6 +596,11 @@ case "${host_os}" in
          AC_MSG_ERROR(dlopen not found, required by Audacity)
       fi
 
+      AC_SEARCH_LIBS([XML_ParserCreate], [expat])
+      if [[ "$ac_cv_search_expat" = no ]]; then
+         AC_MSG_ERROR(expat not found, required by Audacity)
+      fi
+
       AC_SUBST(HAVE_GTK)
       PKG_CHECK_MODULES(GTK, gtk+-2.0, have_gtk=yes, have_gtk=no)
       if [[ "$have_gtk" = "yes" ]]

m4/audacity_checklib_libid3tag.m4

@@ -49,6 +49,7 @@ AC_DEFUN([AUDACITY_CHECKLIB_LIBID3TAG], [
       LIBID3TAG_LOCAL_LIBS="libid3tag.a"
       LIBID3TAG_LOCAL_CXXFLAGS='-I$(top_srcdir)/lib-src/libid3tag'
       LIBID3TAG_LOCAL_CPPSYMBOLS="USE_LIBID3TAG"
+      LIBS="${LIBS} -lz"
       AC_MSG_NOTICE([libid3tag libraries are available in the local tree])
    else
       LIBID3TAG_LOCAL_AVAILABLE="no"

m4/audacity_checklib_portaudio.m4

@@ -44,7 +44,7 @@ AC_DEFUN([AUDACITY_CHECKLIB_PORTAUDIO], [
       PORTAUDIO_LOCAL_CXXFLAGS='-I$(top_srcdir)/lib-src/portaudio-v19/include'
 
       dnl set up configuring portaudio
-      PORTAUDIO_LOCAL_CONFIGURE_ARGS="--with-pa-include=../portaudio-v19/include"
+      PORTAUDIO_LOCAL_CONFIGURE_ARGS="--with-pa-include=$(pwd)/lib-src/portaudio-v19/include"
 
       AC_MSG_NOTICE([portaudio19 library is available in the local tree])
    else