Patch libffi to work with newer gcc.

Refs #59 and libffi/libffi#760.

buildroot-customizations/board/inmusic/common/patches/libffi/3.4.4/Forward-declare-open-temp-exec-file.patch

@@ -0,0 +1,42 @@
+From cbfb9b436ab13e4b4aba867d061e11d7f89a351c Mon Sep 17 00:00:00 2001
+From: serge-sans-paille <[email protected]>
+Date: Wed, 1 Feb 2023 18:09:25 +0100
+Subject: [PATCH] Forward declare open_temp_exec_file
+
+It's defined in closures.c and used in tramp.c.
+Also declare it as an hidden symbol, as it should be.
+---
+ include/ffi_common.h | 4 ++++
+ src/tramp.c          | 4 ++++
+ 2 files changed, 8 insertions(+)
+
+diff --git a/include/ffi_common.h b/include/ffi_common.h
+index 2bd31b03d..c53a79493 100644
+--- a/include/ffi_common.h
++++ b/include/ffi_common.h
+@@ -128,6 +128,10 @@ void *ffi_data_to_code_pointer (void *data) FFI_HIDDEN;
+    static trampoline. */
+ int ffi_tramp_is_present (void *closure) FFI_HIDDEN;
+
++/* Return a file descriptor of a temporary zero-sized file in a
++   writable and executable filesystem. */
++int open_temp_exec_file(void) FFI_HIDDEN;
++
+ /* Extended cif, used in callback from assembly routine */
+ typedef struct
+ {
+diff --git a/src/tramp.c b/src/tramp.c
+index b9d273a1a..c3f4c9933 100644
+--- a/src/tramp.c
++++ b/src/tramp.c
+@@ -39,6 +39,10 @@
+ #ifdef __linux__
+ #define _GNU_SOURCE 1
+ #endif
++
++#include <ffi.h>
++#include <ffi_common.h>
++
+ #include <stdio.h>
+ #include <unistd.h>
+ #include <stdlib.h>

compile-buildroot.sh

@@ -56,9 +56,20 @@ export PATH="${PATH// /}"
 
 buildroot_path="buildroot/$(get_buildroot_version)"
 
+BR2_GLOBAL_PATCH_DIR=""
+for d in common "${device_id_lowercase}"; do
+  if [ -d "${SCRIPT_DIR}/buildroot-customizations/board/inmusic/$d/patches" ]; then
+    if [ -n "${BR2_GLOBAL_PATCH_DIR}" ]; then
+      BR2_GLOBAL_PATCH_DIR="${BR2_GLOBAL_PATCH_DIR} "
+    fi
+    BR2_GLOBAL_PATCH_DIR="${BR2_GLOBAL_PATCH_DIR}${SCRIPT_DIR}/buildroot-customizations/board/inmusic/$d/patches"
+  fi
+done
+
 make_flags=(
   -C "${buildroot_path}"
   BR2_EXTERNAL=../../buildroot-customizations
+  BR2_GLOBAL_PATCH_DIR="${BR2_GLOBAL_PATCH_DIR}"
 )
 
 if [ -n "${BR2_JLEVEL:-}" ]; then

configure-buildroot.sh

@@ -16,5 +16,24 @@ if [ -z "$config_target" ]; then
     config_target=nconfig
   fi
 fi
-make -C "$buildroot_path" -j$(nproc) BR2_EXTERNAL=../../buildroot-customizations "$config_target"
+
+BR2_GLOBAL_PATCH_DIR=""
+for d in common "${device_id_lowercase}"; do
+  if [ -d "${SCRIPT_DIR}/buildroot-customizations/board/inmusic/$d/patches" ]; then
+    if [ -n "${BR2_GLOBAL_PATCH_DIR}" ]; then
+      BR2_GLOBAL_PATCH_DIR="${BR2_GLOBAL_PATCH_DIR} "
+    fi
+    BR2_GLOBAL_PATCH_DIR="${BR2_GLOBAL_PATCH_DIR}${SCRIPT_DIR}/buildroot-customizations/board/inmusic/$d/patches"
+  fi
+done
+
+make_flags=(
+  -C "${buildroot_path}"
+  BR2_EXTERNAL=../../buildroot-customizations
+  BR2_GLOBAL_PATCH_DIR="${BR2_GLOBAL_PATCH_DIR}"
+)
+
+make \
+  "${make_flags[@]}" \
+  "$config_target"
 cp -v "$buildroot_path/.config" buildroot-config