Use pkg-config in the libxml configure check.

configure

@@ -311,7 +311,7 @@ ac_includes_default="\
 # include <unistd.h>
 #endif"
 
-ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS DLLDEFS build build_cpu build_vendor build_os host host_cpu host_vendor host_os WIN16_FILES WIN16_INSTALL SET_MAKE CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC EXEEXT OBJEXT CXX CXXFLAGS ac_ct_CXX CPPBIN ac_ct_CPPBIN TOOLSDIR CPP X_CFLAGS X_PRE_LIBS X_LIBS X_EXTRA_LIBS LEX LEXLIB LEX_OUTPUT_ROOT XLEX BISON AS ac_ct_AS LD ac_ct_LD AR ac_ct_AR RANLIB ac_ct_RANLIB STRIP ac_ct_STRIP WINDRES ac_ct_WINDRES LN_S LN EGREP LDCONFIG INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA LINT LINTFLAGS FONTFORGE LIBPTHREAD XLIB XFILES OPENGLFILES GLU32FILES OPENGL_LIBS GLUT_LIBS GLUT32FILES NASLIBS XML2LIBS XML2INCL CURSESLIBS sane_devel SANELIBS SANEINCL ICULIBS LCMSLIBS LDAPLIBS FREETYPELIBS FREETYPEINCL ft_devel ft_devel2 FONTSSUBDIRS ARTSCCONFIG ARTSLIBS ARTSINCL ESDCONFIG ESDLIBS ESDINCL ALSALIBS AUDIOIOLIBS EXTRACFLAGS DLLEXT DLLFLAGS DLLIBS LDSHARED LDDLLFLAGS LIBEXT IMPLIBEXT DLLTOOL ac_ct_DLLTOOL DLLWRAP ac_ct_DLLWRAP LDEXECFLAGS LDLIBWINEFLAGS COREFOUNDATIONLIB IOKITLIB CROSSTEST CROSSCC CROSSWINDRES LDPATH CRTLIBS SOCKETLIBS WINE_BINARIES MAIN_BINARY LDD LIBOBJS LTLIBOBJS'
+ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS DLLDEFS build build_cpu build_vendor build_os host host_cpu host_vendor host_os WIN16_FILES WIN16_INSTALL SET_MAKE CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC EXEEXT OBJEXT CXX CXXFLAGS ac_ct_CXX CPPBIN ac_ct_CPPBIN TOOLSDIR CPP X_CFLAGS X_PRE_LIBS X_LIBS X_EXTRA_LIBS LEX LEXLIB LEX_OUTPUT_ROOT XLEX BISON AS ac_ct_AS LD ac_ct_LD AR ac_ct_AR RANLIB ac_ct_RANLIB STRIP ac_ct_STRIP WINDRES ac_ct_WINDRES LN_S LN EGREP LDCONFIG INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA LINT LINTFLAGS FONTFORGE PKG_CONFIG LIBPTHREAD XLIB XFILES OPENGLFILES GLU32FILES OPENGL_LIBS GLUT_LIBS GLUT32FILES NASLIBS XML2LIBS XML2INCL CURSESLIBS sane_devel SANELIBS SANEINCL ICULIBS LCMSLIBS LDAPLIBS FREETYPELIBS FREETYPEINCL ft_devel ft_devel2 FONTSSUBDIRS ARTSCCONFIG ARTSLIBS ARTSINCL ESDCONFIG ESDLIBS ESDINCL ALSALIBS AUDIOIOLIBS EXTRACFLAGS DLLEXT DLLFLAGS DLLIBS LDSHARED LDDLLFLAGS LIBEXT IMPLIBEXT DLLTOOL ac_ct_DLLTOOL DLLWRAP ac_ct_DLLWRAP LDEXECFLAGS LDLIBWINEFLAGS COREFOUNDATIONLIB IOKITLIB CROSSTEST CROSSCC CROSSWINDRES LDPATH CRTLIBS SOCKETLIBS WINE_BINARIES MAIN_BINARY LDD LIBOBJS LTLIBOBJS'
 ac_subst_files='MAKE_RULES MAKE_DLL_RULES MAKE_TEST_RULES MAKE_LIB_RULES MAKE_PROG_RULES'
 
 # Initialize some variables set by options.
@@ -5640,6 +5640,47 @@ fi
 done
 test -n "$FONTFORGE" || FONTFORGE="false"
 
+for ac_prog in pkg-config
+do
+  # Extract the first word of "$ac_prog", so it can be a program name with args.
+set dummy $ac_prog; ac_word=$2
+echo "$as_me:$LINENO: checking for $ac_word" >&5
+echo $ECHO_N "checking for $ac_word... $ECHO_C" >&6
+if test "${ac_cv_prog_PKG_CONFIG+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  if test -n "$PKG_CONFIG"; then
+  ac_cv_prog_PKG_CONFIG="$PKG_CONFIG" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  test -z "$as_dir" && as_dir=.
+  for ac_exec_ext in '' $ac_executable_extensions; do
+  if $as_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+    ac_cv_prog_PKG_CONFIG="$ac_prog"
+    echo "$as_me:$LINENO: found $as_dir/$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+done
+
+fi
+fi
+PKG_CONFIG=$ac_cv_prog_PKG_CONFIG
+if test -n "$PKG_CONFIG"; then
+  echo "$as_me:$LINENO: result: $PKG_CONFIG" >&5
+echo "${ECHO_T}$PKG_CONFIG" >&6
+else
+  echo "$as_me:$LINENO: result: no" >&5
+echo "${ECHO_T}no" >&6
+fi
+
+  test -n "$PKG_CONFIG" && break
+done
+test -n "$PKG_CONFIG" || PKG_CONFIG="false"
+
 
 
 
@@ -8508,8 +8549,12 @@ XML2LIBS=""
 
 XML2INCL=""
 
-ac_save_CPPFLAGS="$CPPFLAGS"
-CPPFLAGS="$CPPFLAGS -I/usr/include/libxml2"
+if test "$PKG_CONFIG" != "false"
+then
+    ac_save_CPPFLAGS="$CPPFLAGS"
+    ac_xml_libs="`$PKG_CONFIG --libs libxml-2.0`"
+    ac_xml_cflags="`$PKG_CONFIG --cflags libxml-2.0`"
+    CPPFLAGS="$CPPFLAGS $ac_xml_cflags"
 
 for ac_header in libxml/parser.h
 do
@@ -8654,13 +8699,13 @@ if test `eval echo '${'$as_ac_Header'}'` = yes; then
   cat >>confdefs.h <<_ACEOF
 #define `echo "HAVE_$ac_header" | $as_tr_cpp` 1
 _ACEOF
- echo "$as_me:$LINENO: checking for xmlReadIO in -lxml2" >&5
-echo $ECHO_N "checking for xmlReadIO in -lxml2... $ECHO_C" >&6
-if test "${ac_cv_lib_xml2_xmlReadIO+set}" = set; then
+ echo "$as_me:$LINENO: checking for xmlParseMemory in -lxml2" >&5
+echo $ECHO_N "checking for xmlParseMemory in -lxml2... $ECHO_C" >&6
+if test "${ac_cv_lib_xml2_xmlParseMemory+set}" = set; then
   echo $ECHO_N "(cached) $ECHO_C" >&6
 else
   ac_check_lib_save_LIBS=$LIBS
-LIBS="-lxml2  $LIBS"
+LIBS="-lxml2 $ac_xml_libs $LIBS"
 cat >conftest.$ac_ext <<_ACEOF
 /* confdefs.h.  */
 _ACEOF
@@ -8674,11 +8719,11 @@ extern "C"
 #endif
 /* We use char because int might match the return type of a gcc2
    builtin and then its argument prototype would still apply.  */
-char xmlReadIO ();
+char xmlParseMemory ();
 int
 main ()
 {
-xmlReadIO ();
+xmlParseMemory ();
   ;
   return 0;
 }
@@ -8704,34 +8749,35 @@ if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
   ac_status=$?
   echo "$as_me:$LINENO: \$? = $ac_status" >&5
   (exit $ac_status); }; }; then
-  ac_cv_lib_xml2_xmlReadIO=yes
+  ac_cv_lib_xml2_xmlParseMemory=yes
 else
   echo "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-ac_cv_lib_xml2_xmlReadIO=no
+ac_cv_lib_xml2_xmlParseMemory=no
 fi
 rm -f conftest.err conftest.$ac_objext \
       conftest$ac_exeext conftest.$ac_ext
 LIBS=$ac_check_lib_save_LIBS
 fi
-echo "$as_me:$LINENO: result: $ac_cv_lib_xml2_xmlReadIO" >&5
-echo "${ECHO_T}$ac_cv_lib_xml2_xmlReadIO" >&6
-if test $ac_cv_lib_xml2_xmlReadIO = yes; then
+echo "$as_me:$LINENO: result: $ac_cv_lib_xml2_xmlParseMemory" >&5
+echo "${ECHO_T}$ac_cv_lib_xml2_xmlParseMemory" >&6
+if test $ac_cv_lib_xml2_xmlParseMemory = yes; then
 
 cat >>confdefs.h <<\_ACEOF
 #define HAVE_LIBXML2 1
 _ACEOF
 
-         XML2LIBS="-lxml2"
-         XML2INCL="-I/usr/include/libxml2"
+             XML2LIBS="$ac_xml_libs"
+             XML2INCL="$ac_xml_cflags"
 fi
 
 fi
 
 done
 
-CPPFLAGS="$ac_save_CPPFLAGS"
+    CPPFLAGS="$ac_save_CPPFLAGS"
+fi
 
 CURSESLIBS=""
 if test "x$with_curses" != "xno"
@@ -19057,6 +19103,7 @@ s,@INSTALL_DATA@,$INSTALL_DATA,;t t
 s,@LINT@,$LINT,;t t
 s,@LINTFLAGS@,$LINTFLAGS,;t t
 s,@FONTFORGE@,$FONTFORGE,;t t
+s,@PKG_CONFIG@,$PKG_CONFIG,;t t
 s,@LIBPTHREAD@,$LIBPTHREAD,;t t
 s,@XLIB@,$XLIB,;t t
 s,@XFILES@,$XFILES,;t t

configure.ac

@@ -134,6 +134,7 @@ AC_SUBST(LINTFLAGS)
 
 dnl Check for various programs
 AC_CHECK_PROGS(FONTFORGE, fontforge, false)
+AC_CHECK_PROGS(PKG_CONFIG, pkg-config, false)
 
 dnl **** Check for some libraries ****
 
@@ -434,14 +435,19 @@ dnl **** Check for libxml2 ****
 
 AC_SUBST(XML2LIBS,"")
 AC_SUBST(XML2INCL,"")
-ac_save_CPPFLAGS="$CPPFLAGS"
-CPPFLAGS="$CPPFLAGS -I/usr/include/libxml2"
-AC_CHECK_HEADERS(libxml/parser.h,
-    [AC_CHECK_LIB(xml2, xmlReadIO,
-        [AC_DEFINE(HAVE_LIBXML2, 1, [Define if you have the libxml2 library])
-         XML2LIBS="-lxml2"
-         XML2INCL="-I/usr/include/libxml2"])])
-CPPFLAGS="$ac_save_CPPFLAGS"
+if test "$PKG_CONFIG" != "false"
+then
+    ac_save_CPPFLAGS="$CPPFLAGS"
+    ac_xml_libs="`$PKG_CONFIG --libs libxml-2.0`"
+    ac_xml_cflags="`$PKG_CONFIG --cflags libxml-2.0`"
+    CPPFLAGS="$CPPFLAGS $ac_xml_cflags"
+    AC_CHECK_HEADERS(libxml/parser.h,
+        [AC_CHECK_LIB(xml2, xmlParseMemory,
+            [AC_DEFINE(HAVE_LIBXML2, 1, [Define if you have the libxml2 library])
+             XML2LIBS="$ac_xml_libs"
+             XML2INCL="$ac_xml_cflags"],,$ac_xml_libs)])
+    CPPFLAGS="$ac_save_CPPFLAGS"
+fi
 
 dnl **** Check which curses lib to use ***
 CURSESLIBS=""