build-sys: take preset CFLAGS into account

diff --git a/bootstrap.sh b/bootstrap.sh
index 79e0a7dcef8237f35e65c6fc7f02598371a0cbe8..970e884e5813cc745768832edaf40c8fbe43ca98 100755 (executable)
--- a/bootstrap.sh
+++ b/bootstrap.sh
@@ -94,7 +94,7 @@ else
     run_versioned automake "$VERSION" --copy --foreign --add-missing
 
     if test "x$NOCONFIGURE" = "x"; then
-        CFLAGS="-g -O0" ./configure --sysconfdir=/etc --localstatedir=/var --enable-force-preopen "$@"
+        CFLAGS="$CFLAGS -g -O0" ./configure --sysconfdir=/etc --localstatedir=/var --enable-force-preopen "$@"
         make clean
     fi
 fi