From f77c72f3718711ce2f29787e40ec4638e2be6db8 Mon Sep 17 00:00:00 2001
From: Georgi Gerganov <ggerganov@gmail.com>
Date: Sun, 7 Jan 2024 13:06:57 +0200
Subject: [PATCH] ggml : fix null backend dereference (#4807)

* ggml : fix null backend dereference

* ggml : also check ggml_backend_is_cpu
---
 ggml-backend.c | 2 +-
 ggml-cuda.cu   | 2 +-
 ggml-metal.m   | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/ggml-backend.c b/ggml-backend.c
index 56f96c367..8d66c5605 100644
--- a/ggml-backend.c
+++ b/ggml-backend.c
@@ -703,7 +703,7 @@ ggml_backend_t ggml_backend_cpu_init(void) {
 }
 
 bool ggml_backend_is_cpu(ggml_backend_t backend) {
-    return backend->iface.get_name == ggml_backend_cpu_name;
+    return backend && backend->iface.get_name == ggml_backend_cpu_name;
 }
 
 void ggml_backend_cpu_set_n_threads(ggml_backend_t backend_cpu, int n_threads) {
diff --git a/ggml-cuda.cu b/ggml-cuda.cu
index 032d7e986..ee82f68d7 100644
--- a/ggml-cuda.cu
+++ b/ggml-cuda.cu
@@ -10140,7 +10140,7 @@ ggml_backend_t ggml_backend_cuda_init(int device) {
 }
 
 bool ggml_backend_is_cuda(ggml_backend_t backend) {
-    return backend->iface.get_name == ggml_backend_cuda_name;
+    return backend && backend->iface.get_name == ggml_backend_cuda_name;
 }
 
 int ggml_backend_cuda_get_device_count() {
diff --git a/ggml-metal.m b/ggml-metal.m
index e3d76b9d3..00b377a3e 100644
--- a/ggml-metal.m
+++ b/ggml-metal.m
@@ -2749,7 +2749,7 @@ ggml_backend_t ggml_backend_metal_init(void) {
 }
 
 bool ggml_backend_is_metal(ggml_backend_t backend) {
-    return backend->iface.get_name == ggml_backend_metal_name;
+    return backend && backend->iface.get_name == ggml_backend_metal_name;
 }
 
 void ggml_backend_metal_set_n_cb(ggml_backend_t backend, int n_cb) {