Fix most compiler warnings in the boot and code segments (#674)

* Less warnings in boot & code segments

* few more warnings gone

* Ran formatter

* z_view warning gone

* -> 1

* f31 -> 31

* Remove function casts

* Few more small improvements

* Separate declaration and assignment in func_80091738 and Item_Give

Co-authored-by: Thar0 <maximilianc64@gmail.com>

src/code/debug_malloc.c

@@ -8,7 +8,7 @@ s32 gDebugArenaLogSeverity = LOG_SEVERITY_ERROR;
 Arena sDebugArena;
 
 void DebugArena_CheckPointer(void* ptr, u32 size, const char* name, const char* action) {
-    if (!ptr) {
+    if (ptr == NULL) {
         if (gDebugArenaLogSeverity >= LOG_SEVERITY_ERROR) {
             // "%s: %u bytes %s failed\n"
             osSyncPrintf("%s: %u バイトの%sに失敗しました\n", name, size, action);
@@ -22,29 +22,29 @@ void DebugArena_CheckPointer(void* ptr, u32 size, const char* name, const char*
 }
 
 void* DebugArena_Malloc(u32 size) {
-    void* ptr;
-    ptr = __osMalloc(&sDebugArena, size);
+    void* ptr = __osMalloc(&sDebugArena, size);
+
     DebugArena_CheckPointer(ptr, size, "debug_malloc", "確保"); // Secure
     return ptr;
 }
 
 void* DebugArena_MallocDebug(u32 size, const char* file, s32 line) {
-    void* ptr;
-    ptr = __osMallocDebug(&sDebugArena, size, file, line);
+    void* ptr = __osMallocDebug(&sDebugArena, size, file, line);
+
     DebugArena_CheckPointer(ptr, size, "debug_malloc_DEBUG", "確保"); // Secure
     return ptr;
 }
 
 void* DebugArena_MallocR(u32 size) {
-    void* ptr;
-    ptr = __osMallocR(&sDebugArena, size);
+    void* ptr = __osMallocR(&sDebugArena, size);
+
     DebugArena_CheckPointer(ptr, size, "debug_malloc_r", "確保"); // Secure
     return ptr;
 }
 
 void* DebugArena_MallocRDebug(u32 size, const char* file, s32 line) {
-    void* ptr;
-    ptr = __osMallocRDebug(&sDebugArena, size, file, line);
+    void* ptr = __osMallocRDebug(&sDebugArena, size, file, line);
+
     DebugArena_CheckPointer(ptr, size, "debug_malloc_r_DEBUG", "確保"); // Secure
     return ptr;
 }
@@ -71,11 +71,10 @@ void DebugArena_FreeDebug(void* ptr, const char* file, s32 line) {
 
 void* DebugArena_Calloc(u32 num, u32 size) {
     void* ret;
-    u32 n;
+    u32 n = num * size;
 
-    n = num * size;
     ret = __osMalloc(&sDebugArena, n);
-    if (ret) {
+    if (ret != NULL) {
         bzero(ret, n);
     }
 
@@ -83,7 +82,7 @@ void* DebugArena_Calloc(u32 num, u32 size) {
     return ret;
 }
 
-void DebugArena_Display() {
+void DebugArena_Display(void) {
     // Zelda heap display (devs forgot to change "Zelda" to "Debug" apparently)
     osSyncPrintf("ゼルダヒープ表示\n");
     __osDisplayArena(&sDebugArena);
@@ -93,7 +92,7 @@ void DebugArena_GetSizes(u32* outMaxFree, u32* outFree, u32* outAlloc) {
     ArenaImpl_GetSizes(&sDebugArena, outMaxFree, outFree, outAlloc);
 }
 
-void DebugArena_Check() {
+void DebugArena_Check(void) {
     __osCheckArena(&sDebugArena);
 }
 
@@ -102,11 +101,11 @@ void DebugArena_Init(void* start, u32 size) {
     __osMallocInit(&sDebugArena, start, size);
 }
 
-void DebugArena_Cleanup() {
+void DebugArena_Cleanup(void) {
     gDebugArenaLogSeverity = LOG_SEVERITY_NOLOG;
     __osMallocCleanup(&sDebugArena);
 }
 
-u8 DebugArena_IsInitalized() {
+u8 DebugArena_IsInitalized(void) {
     return __osMallocIsInitalized(&sDebugArena);
 }