kernel: Do not invoke memalign with 0 as the alignment argument.

The memalign() function has special semantics for its arguments
even when -fno-builtin is enabled, it seems (that may be a problem
on Clang's part, however.) The alloc_align attribute, which we apply
to the memalign_etc function, does not seem to have the same problems;
at least its documentation at GCC gives no indication that 0 is not a
legal value to pass.

Change-Id: Ie5ba090b924ac3577775165d20f11f9696be97f3

src/system/kernel/guarded_heap.cpp

@@ -562,7 +562,7 @@ guarded_heap_realloc(void* address, size_t newSize)
 	if (oldSize == newSize)
 		return address;
 
-	void* newBlock = memalign(0, newSize);
+	void* newBlock = malloc(newSize);
 	if (newBlock == NULL)
 		return NULL;
 
@@ -974,7 +974,7 @@ realloc(void* address, size_t newSize)
 	}
 
 	if (address == NULL)
-		return memalign(0, newSize);
+		return malloc(newSize);
 
 	return guarded_heap_realloc(address, newSize);
 }

src/system/kernel/heap.cpp

@@ -1864,7 +1864,7 @@ heap_realloc(heap_allocator *heap, void *address, void **newAddress,
 #endif
 
 	// if not, allocate a new chunk of memory
-	*newAddress = memalign(0, newSize);
+	*newAddress = malloc(newSize);
 	T(Reallocate((addr_t)address, (addr_t)*newAddress, newSize));
 	if (*newAddress == NULL) {
 		// we tried but it didn't work out, but still the operation is done
@@ -2349,7 +2349,7 @@ free_etc(void *address, uint32 flags)
 void *
 malloc(size_t size)
 {
-	return memalign(0, size);
+	return memalign_etc(0, size, 0);
 }
 
 
@@ -2410,7 +2410,7 @@ realloc(void *address, size_t newSize)
 	}
 
 	if (address == NULL)
-		return memalign(0, newSize);
+		return malloc(newSize);
 
 	if (newSize == 0) {
 		free(address);
@@ -2455,7 +2455,7 @@ realloc(void *address, size_t newSize)
 			}
 
 			// have to allocate/copy/free - TODO maybe resize the area instead?
-			newAddress = memalign(0, newSize);
+			newAddress = malloc(newSize);
 			if (newAddress == NULL) {
 				dprintf("realloc(): failed to allocate new block of %ld bytes\n",
 					newSize);
@@ -2482,7 +2482,7 @@ realloc(void *address, size_t newSize)
 void *
 calloc(size_t numElements, size_t size)
 {
-	void *address = memalign(0, numElements * size);
+	void *address = malloc(numElements * size);
 	if (address != NULL)
 		memset(address, 0, numElements * size);