* builds/unix/configure.raw: Copy -isysroot option from CFLAGS to LDFLAGS, if required
diff --git a/builds/unix/configure.raw b/builds/unix/configure.raw
index 26a63c7..2015aac 100644
--- a/builds/unix/configure.raw
+++ b/builds/unix/configure.raw
@@ -171,6 +171,32 @@
fi
+# check Apple "-isysroot" option and duplicate it to LDFLAGS if required
+# Apple TechNote 2137 recommends to include it in CFLAGS but not in LDFLAGS.
+
+AC_MSG_CHECKING([CFLAGS includes -isysroot option])
+case "$CFLAGS" in
+ *sysroot* )
+ AC_MSG_RESULT([yes])
+ AC_MSG_CHECKING([LDFLAGS includes -isysroot option])
+ case "$LDFLAGS" in
+ *sysroot* )
+ AC_MSG_RESULT([yes])
+ ;;
+ *)
+ AC_MSG_RESULT([no])
+ isysroot_dir=`echo ${CFLAGS} | tr '\t' ' ' | sed 's/^.*-isysroot *//;s/ .*//'`
+ AC_MSG_WARN(-isysroot ${isysroot_dir} is added to LDFLAGS)
+ LDFLAGS="-isysroot ${isysroot_dir} ${LDFLAGS}"
+ ;;
+ esac
+ ;;
+ *)
+ AC_MSG_RESULT([no])
+ ;;
+esac
+
+
# Whether to use Mac OS resource-based fonts.
# don't quote AS_HELP_STRING!