diff --git a/ggml-backend.c b/ggml-backend.c
index 25d9c98d5..535426b9a 100644
--- a/ggml-backend.c
+++ b/ggml-backend.c
@@ -1006,7 +1006,7 @@ static void sched_split_graph(ggml_backend_sched_t sched, struct ggml_cgraph * g
     // pass 2: assign backends to ops from current assignments
     // start from the end and assign the same backend to previous ops
 
-    // expand gpu backends (ie non last prio) up and down, ignoring cpu
+    // expand gpu backends (i.e. non last prio) up and down, ignoring cpu
     // thus, cpu will never be used unless weights are on cpu, or there are no gpu ops between cpu ops
 
     // pass 2.1 expand gpu up
diff --git a/llama.h b/llama.h
index 5dc4c9357..d387ad77b 100644
--- a/llama.h
+++ b/llama.h
@@ -185,9 +185,11 @@ extern "C" {
     struct llama_model_params {
         int32_t n_gpu_layers; // number of layers to store in VRAM
         enum llama_split_mode split_mode; // how to split the model across multiple GPUs
-        // the GPU that is used for the model (LLAMA_SPLIT_NONE),
-        // for small tensors and intermediate results (LLAMA_SPLIT_ROW)
-        // ignored for LLAMA_SPLIT_LAYER
+        
+        // main_gpu interpretation depends on split_mode:
+        // LLAMA_SPLIT_NONE: the GPU that is used for the entire model
+        // LLAMA_SPLIT_ROW: the GPU that is used for small tensors and intermediate results
+        // LLAMA_SPLIT_LAYER: ignored
         int32_t main_gpu;
         // proportion of the model (layers or rows) to offload to each GPU, size: LLAMA_MAX_DEVICES
         const float * tensor_split;
diff --git a/tests/test-backend-ops.cpp b/tests/test-backend-ops.cpp
index e27f9f284..d9b8b106a 100644
--- a/tests/test-backend-ops.cpp
+++ b/tests/test-backend-ops.cpp
@@ -468,7 +468,7 @@ struct test_case {
             GGML_UNUSED(index);
         };
 
-        bool cmp_ok = ggml_backend_compare_graph_backend(backend1, backend2, gf, callback, &ud);
+        const bool cmp_ok = ggml_backend_compare_graph_backend(backend1, backend2, gf, callback, &ud);
 
         if (!cmp_ok) {
             printf("compare failed ");