Make rb_aligned_malloc private

It is not used anywhere else.

gc.c

@@ -2104,6 +2104,40 @@ heap_page_free(rb_objspace_t *objspace, struct heap_page *page)
     free(page);
 }
 
+static void *
+rb_aligned_malloc(size_t alignment, size_t size)
+{
+    /* alignment must be a power of 2 */
+    GC_ASSERT(((alignment - 1) & alignment) == 0);
+    GC_ASSERT(alignment % sizeof(void*) == 0);
+
+    void *res;
+
+#if defined __MINGW32__
+    res = __mingw_aligned_malloc(size, alignment);
+#elif defined _WIN32
+    void *_aligned_malloc(size_t, size_t);
+    res = _aligned_malloc(size, alignment);
+#elif defined(HAVE_POSIX_MEMALIGN)
+    if (posix_memalign(&res, alignment, size) != 0) {
+        return NULL;
+    }
+#elif defined(HAVE_MEMALIGN)
+    res = memalign(alignment, size);
+#else
+    char* aligned;
+    res = malloc(alignment + size + sizeof(void*));
+    aligned = (char*)res + alignment + sizeof(void*);
+    aligned -= ((VALUE)aligned & (alignment - 1));
+    ((void**)aligned)[-1] = res;
+    res = (void*)aligned;
+#endif
+
+    GC_ASSERT((uintptr_t)res % alignment == 0);
+
+    return res;
+}
+
 static void
 heap_pages_free_unused_pages(rb_objspace_t *objspace)
 {
@@ -11630,40 +11664,6 @@ rb_memerror(void)
     EC_JUMP_TAG(ec, TAG_RAISE);
 }
 
-void *
-rb_aligned_malloc(size_t alignment, size_t size)
-{
-    /* alignment must be a power of 2 */
-    GC_ASSERT(((alignment - 1) & alignment) == 0);
-    GC_ASSERT(alignment % sizeof(void*) == 0);
-
-    void *res;
-
-#if defined __MINGW32__
-    res = __mingw_aligned_malloc(size, alignment);
-#elif defined _WIN32
-    void *_aligned_malloc(size_t, size_t);
-    res = _aligned_malloc(size, alignment);
-#elif defined(HAVE_POSIX_MEMALIGN)
-    if (posix_memalign(&res, alignment, size) != 0) {
-        return NULL;
-    }
-#elif defined(HAVE_MEMALIGN)
-    res = memalign(alignment, size);
-#else
-    char* aligned;
-    res = malloc(alignment + size + sizeof(void*));
-    aligned = (char*)res + alignment + sizeof(void*);
-    aligned -= ((VALUE)aligned & (alignment - 1));
-    ((void**)aligned)[-1] = res;
-    res = (void*)aligned;
-#endif
-
-    GC_ASSERT((uintptr_t)res % alignment == 0);
-
-    return res;
-}
-
 static void
 rb_aligned_free(void *ptr, size_t size)
 {

internal/gc.h

@@ -199,10 +199,6 @@ VALUE rb_objspace_gc_enable(struct rb_objspace *);
 VALUE rb_objspace_gc_disable(struct rb_objspace *);
 void ruby_gc_set_params(void);
 void rb_copy_wb_protected_attribute(VALUE dest, VALUE obj);
-#if __has_attribute(alloc_align)
-__attribute__((__alloc_align__(1)))
-#endif
-RUBY_ATTR_MALLOC void *rb_aligned_malloc(size_t, size_t) RUBY_ATTR_ALLOC_SIZE((2));
 size_t rb_size_mul_or_raise(size_t, size_t, VALUE); /* used in compile.c */
 size_t rb_size_mul_add_or_raise(size_t, size_t, size_t, VALUE); /* used in iseq.h */
 size_t rb_malloc_grow_capa(size_t current_capacity, size_t type_size);