diff --git a/config.lib b/config.lib
--- a/config.lib
+++ b/config.lib
@@ -1434,7 +1434,9 @@ make_cflags_and_ldflags() {
 	# Also make makedepend aware of compiler's built-in defines.
 	if [ "$with_makedepend" != "0" ] || [ "$enable_builtin_depend" != "0" ]; then
 		cflags_makedep="`echo | $cxx_host -E -x c++ -dM - | sed 's@.define @-D@g;s@ .*@ @g;s@(.*)@@g' | tr -d '\r\n'`"
-		cflags_makedep="$cflags_makedep `echo "$CFLAGS" | sed 's@ /@ -@g;s@-I[ ]*[^ ]*@@g'`"
+
+		# Please escape ALL " within ` because e.g. "" terminates the string in some sh implementations
+		cflags_makedep="$cflags_makedep `echo \"$CFLAGS\" | sed 's@ /@ -@g;s@-I[ ]*[^ ]*@@g'`"
 	else
 		makedepend=""
 	fi