gstreamer 1.14.4 building error with buildroot - gstreamer

Question

I ran into the following error when building gstreamer 1.14.4 :
/build/gstreamer1-1.14.4/libs/gst/controller »
CC libgstcontroller_1.0_la-controller-enumtypes.lo
controller-enumtypes.c:6:1: error: « \ » stray in program
\#include "gstinterpolationcontrolsource.h"
^
controller-enumtypes.c:6:2: error: « # » stray in program
\#include "gstinterpolationcontrolsource.h"
^
controller-enumtypes.c:6:11: error: expected « = », « , », « ; », « asm » or « __attribute__ » before string constant
\#include "gstinterpolationcontrolsource.h"
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
controller-enumtypes.c:7:1: error: « \ » stray in program
\#include "gstlfocontrolsource.h"
^
controller-enumtypes.c:7:2: error: « # » stray in program
\#include "gstlfocontrolsource.h"
...
I am compiling for Raspberry Pi 3 model B+ on Debian Bullseye (GNU Make 4.3, gcc (Debian 10.2.1-6) 10.2.1 20210110) and the cross compiler is arm-buildroot-linux-gnueabihf-gcc-7.4.0. Before that the compilation was ok on Linux Mint Sonya.
It seems to be related to generated code :
/* controller-enumtypes.c */
/* This file is generated by glib-mkenums, do not modify it. This code is licensed under the same license as the containing project. Note that it links to GLib, so must comply with the LGPL linking clauses. */
#include "controller-enumtypes.h"
\#include "gstinterpolationcontrolsource.h"
\#include "gstlfocontrolsource.h"
...
In the line \#include "gstinterpolationcontrolsource.h" there is an extra "\" which is an invalid syntax.
How to properly fix this package with buildroot-2019.02.9 ?
Thank you.

Answer 1

According to https://bugs.gentoo.org/705974, this happens due to the use of make 4.3 on your new machine. make 4.3 was released in January 2020, so it wasn't a version of make that we could have tested back when Buildroot 2019.02 was released.
In the Gentoo bug report above, you can find a patch that solves the issue. However, keep in mind that Buildroot 2019.02.x is no longer maintained: we maintain the long-term support releases during one year.