Fix lib detection with "--with-jsondir" flag

Patch by jabakobob
References #4528

git-svn-id: http://svn.osgeo.org/postgis/trunk@17878 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/configure.ac b/configure.ac
index be9dccf53dfc95725c55256b9e0c8c7d1ff2352f..9af7282e4fb3dc1d6519bb0c45c853ef855470fa 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -929,19 +929,23 @@ if test "$CHECK_JSON" != "no"; then
             else
                     AC_MSG_RESULT([Using user-specified json-c directory: $JSONDIR])
 
+                    JSON_LDFLAGS="-L$JSONDIR/lib"
+                    LIBS_SAVE="$LIBS"
+                    LIBS="$JSON_LDFLAGS"
                     AC_CHECK_FILE("$JSONDIR/include/json-c/json.h",
                                 [
                                     JSON_CPPFLAGS="-I$JSONDIR/include/json-c"
-                                    AC_CHECK_LIB([json-c], [json_object_get], [HAVE_JSON_C=yes; JSON_LDFLAGS="-L$JSONDIR/lib -ljson-c"])
+                                    AC_CHECK_LIB([json-c], [json_object_get], [HAVE_JSON_C=yes; JSON_LDFLAGS="${JSON_LDFLAGS} -ljson-c"])
                                 ],
                                 [
                                     AC_CHECK_FILE("$JSONDIR/include/json/json.h",
                                     [
                                         JSON_CPPFLAGS="-I$JSONDIR/include/json"
-                                        AC_CHECK_LIB([json], [json_object_get], [HAVE_JSON=yes; JSON_LDFLAGS="-L$JSONDIR/lib -ljson"])
+                                        AC_CHECK_LIB([json], [json_object_get], [HAVE_JSON=yes; JSON_LDFLAGS="${JSON_LDFLAGS} -ljson"])
                                     ],
                                     [AC_MSG_ERROR([Could not find header: json.h])])
                                 ])
+                    LIBS="$LIBS_SAVE"
             fi
     elif test ! -z "$PKG_CONFIG"; then
        PKG_CHECK_MODULES([JSONC], [json-c], [