Code cleanup: fix various compiler warnings on clang/macOS.

source/blender/draw/engines/eevee/eevee_bloom.c

@@ -41,7 +41,7 @@ static struct {
 	struct GPUShader *bloom_downsample_sh[2];
 	struct GPUShader *bloom_upsample_sh[2];
 	struct GPUShader *bloom_resolve_sh[2];
-} e_data = {NULL}; /* Engine data */
+} e_data = {{NULL}}; /* Engine data */
 
 extern char datatoc_effect_bloom_frag_glsl[];
 

source/blender/draw/engines/eevee/eevee_screen_raytrace.c

@@ -48,7 +48,7 @@ static struct {
 	/* Theses are just references, not actually allocated */
 	struct GPUTexture *depth_src;
 	struct GPUTexture *color_src;
-} e_data = {NULL}; /* Engine data */
+} e_data = {{NULL}}; /* Engine data */
 
 extern char datatoc_ambient_occlusion_lib_glsl[];
 extern char datatoc_common_view_lib_glsl[];

source/blender/draw/engines/eevee/eevee_subsurface.c

@@ -34,7 +34,7 @@
 
 static struct {
 	struct GPUShader *sss_sh[4];
-} e_data = {NULL}; /* Engine data */
+} e_data = {{NULL}}; /* Engine data */
 
 extern char datatoc_common_view_lib_glsl[];
 extern char datatoc_common_uniforms_lib_glsl[];

source/blender/gpu/intern/gpu_batch_presets.c

@@ -51,7 +51,7 @@ static struct {
 	struct {
 		uint pos, nor;
 	} attr_id;
-} g_presets_3d = {0};
+} g_presets_3d = {{0}};
 
 /* We may want 2D presets later. */
 

source/blender/windowmanager/intern/wm_operators.c

@@ -1814,7 +1814,7 @@ static int wm_operator_tool_set_exec(bContext *C, wmOperator *op)
 {
 	ScrArea *sa = CTX_wm_area(C);
 
-	bToolDef tool_def = {0};
+	bToolDef tool_def = {{0}};
 
 	tool_def.index = RNA_int_get(op->ptr, "index");
 	tool_def.spacetype = sa->spacetype;

source/blender/windowmanager/message_bus/intern/wm_message_bus.c

@@ -40,7 +40,7 @@
 /** \name Public API
  * \{ */
 
-static wmMsgTypeInfo wm_msg_types[WM_MSG_TYPE_NUM] = {NULL};
+static wmMsgTypeInfo wm_msg_types[WM_MSG_TYPE_NUM] = {{{NULL}}};
 
 typedef void (*wmMsgTypeInitFn)(wmMsgTypeInfo *);
 

source/blender/windowmanager/message_bus/intern/wm_message_bus_rna.c

@@ -300,14 +300,14 @@ void WM_msg_subscribe_ID(
         struct wmMsgBus *mbus, ID *id, const wmMsgSubscribeValue *msg_val_params,
         const char *id_repr)
 {
-	wmMsgParams_RNA msg_key_params = {NULL};
+	wmMsgParams_RNA msg_key_params = {{{NULL}}};
 	RNA_id_pointer_create(id, &msg_key_params.ptr);
 	WM_msg_subscribe_rna_params(mbus, &msg_key_params, msg_val_params, id_repr);
 }
 
 void WM_msg_publish_ID(struct wmMsgBus *mbus, ID *id)
 {
-	wmMsgParams_RNA msg_key_params = {NULL};
+	wmMsgParams_RNA msg_key_params = {{{NULL}}};
 	RNA_id_pointer_create(id, &msg_key_params.ptr);
 	WM_msg_publish_rna_params(mbus, &msg_key_params);
 }