chore: Warn about unused return values

include/nds/arm9/dynamicArray.h

@@ -35,6 +35,7 @@ typedef struct DynamicArray
 ///
 /// @return
 ///     A pointer to the data, or NULL on error.
+WARN_UNUSED_RESULT
 void *DynamicArrayInit(DynamicArray *v, unsigned int initialSize);
 
 /// Frees memory allocated by the dynamic array.
@@ -52,6 +53,7 @@ void DynamicArrayDelete(DynamicArray *v);
 ///
 /// @return
 ///     The data or NULL if v is NULL or the index is out of range.
+WARN_UNUSED_RESULT
 void *DynamicArrayGet(DynamicArray *v, unsigned int index);
 
 /// Sets the entry to the supplied value.
@@ -65,6 +67,7 @@ void *DynamicArrayGet(DynamicArray *v, unsigned int index);
 ///
 /// @return
 ///     Returns false if v is NULL or there isn't enough memory, true otherwise.
+WARN_UNUSED_RESULT
 bool DynamicArraySet(DynamicArray *v, unsigned int index, void *item);
 
 #ifdef __cplusplus

include/nds/arm9/linkedlist.h

@@ -16,6 +16,8 @@
 extern "C" {
 #endif
 
+#include <nds/ndstypes.h>
+
 /// A node of the linked list.
 typedef struct LinkedList
 {
@@ -38,6 +40,7 @@ typedef struct LinkedList
 /// @return
 ///     A pointer to the new node, which is also the new front, or NULL if there
 ///     is not enough memory.
+WARN_UNUSED_RESULT
 LinkedList *linkedlistAdd(LinkedList **front, void *data);
 
 /// Removes a node from a linked list.

include/nds/arm9/sprite.h

@@ -386,6 +386,7 @@ u16 *oamGetGfxPtr(OamState *oam, int gfxOffsetIndex);
 ///
 /// @return
 ///     The address in VRAM of the allocated sprite.
+WARN_UNUSED_RESULT
 u16 *oamAllocateGfx(OamState *oam, SpriteSize size, SpriteColorFormat colorFormat);
 
 /// Free VRAM memory obtained with oamAllocateGfx.

include/nds/arm9/videoGL.h

@@ -446,6 +446,7 @@ void glRotatef32i(int angle, int32_t x, int32_t y, int32_t z);
 ///
 /// @return
 ///     1 on success, 0 on failure.
+WARN_UNUSED_RESULT
 int glTexImage2D(int target, int empty1, GL_TEXTURE_TYPE_ENUM type, int sizeX,
                  int sizeY, int empty2, int param, const void *texture);
 
@@ -508,6 +509,7 @@ static inline enum GL_TEXTURE_SIZE_ENUM glTexSizeToEnum(int size)
 ///
 /// @return
 ///     1 on success, 0 on failure.
+WARN_UNUSED_RESULT
 int glColorTableEXT(int target, int empty1, uint16_t width, int empty2,
                     int empty3, const void *table);
 
@@ -529,6 +531,7 @@ int glColorTableEXT(int target, int empty1, uint16_t width, int empty2,
 ///
 /// @return
 ///     1 on success, 0 on failure.
+WARN_UNUSED_RESULT
 int glColorSubTableEXT(int target, int start, int count, int empty1,
                        int empty2, const void *data);
 
@@ -546,6 +549,7 @@ int glColorSubTableEXT(int target, int start, int count, int empty1,
 ///
 /// @return
 ///     1 on success, 0 on failure.
+WARN_UNUSED_RESULT
 int glGetColorTableEXT(int target, int empty1, int empty2, void *table);
 
 /// glAssignColorTable sets the active texture with a palette set with another
@@ -562,6 +566,7 @@ int glGetColorTableEXT(int target, int empty1, int empty2, void *table);
 ///
 /// @return
 ///     1 on success, 0 on failure.
+WARN_UNUSED_RESULT
 int glAssignColorTable(int target, int name);
 
 /// Set parameters for the current texture.
@@ -597,6 +602,7 @@ u32 glGetTexParameter(void);
 ///
 /// @return
 ///     1 on success, 0 on failure.
+WARN_UNUSED_RESULT
 int glGetColorTableParameterEXT(int target, int pname, int *params);
 
 /// Returns the address allocated to the texure named by name.
@@ -649,6 +655,7 @@ int glBindTexture(int target, int name);
 ///
 /// @return
 ///     1 on success, 0 on failure.
+WARN_UNUSED_RESULT
 int glGenTextures(int n, int *names);
 
 /// Deletes the specified number of textures (and associated palettes).
@@ -1457,6 +1464,7 @@ static inline void glCutoffDepth(fixed12d3 wVal)
 ///
 /// @return
 ///     1 on success, 0 on failure
+WARN_UNUSED_RESULT
 int glInit(void);
 
 /// Sets the color of the rear-plane (a.k.a clear color/plane)

include/nds/ndstypes.h

@@ -66,6 +66,10 @@ extern "C" {
 /// for the compiler.
 #define COMPILER_MEMORY_BARRIER() asm volatile("" ::: "memory")
 
+/// Makes the compiler output a warning if the return value of a function is
+/// ignored.
+#define WARN_UNUSED_RESULT __attribute__((warn_unused_result))
+
 // Macros related to the bin2o macro of the Makefile
 #define GETRAW(name)        (name)
 #define GETRAWSIZE(name)    ((int)name##_size)