lavu: move LOCAL_ALIGNED from internal.h to mem_internal.h

That is a more appropriate place for it.

libavutil/mem_internal.h

@@ -21,9 +21,51 @@
 #ifndef AVUTIL_MEM_INTERNAL_H
 #define AVUTIL_MEM_INTERNAL_H
 
+#include "config.h"
+
+#include <stdint.h>
+
 #include "avassert.h"
 #include "mem.h"
 
+// Some broken preprocessors need a second expansion
+// to be forced to tokenize __VA_ARGS__
+#define E1(x) x
+
+#define LOCAL_ALIGNED_A(a, t, v, s, o, ...)             \
+    uint8_t la_##v[sizeof(t s o) + (a)];                \
+    t (*v) o = (void *)FFALIGN((uintptr_t)la_##v, a)
+
+#define LOCAL_ALIGNED_D(a, t, v, s, o, ...)             \
+    DECLARE_ALIGNED(a, t, la_##v) s o;                  \
+    t (*v) o = la_##v
+
+#define LOCAL_ALIGNED(a, t, v, ...) LOCAL_ALIGNED_##a(t, v, __VA_ARGS__)
+
+#if HAVE_LOCAL_ALIGNED
+#   define LOCAL_ALIGNED_4(t, v, ...) E1(LOCAL_ALIGNED_D(4, t, v, __VA_ARGS__,,))
+#else
+#   define LOCAL_ALIGNED_4(t, v, ...) E1(LOCAL_ALIGNED_A(4, t, v, __VA_ARGS__,,))
+#endif
+
+#if HAVE_LOCAL_ALIGNED
+#   define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_D(8, t, v, __VA_ARGS__,,))
+#else
+#   define LOCAL_ALIGNED_8(t, v, ...) E1(LOCAL_ALIGNED_A(8, t, v, __VA_ARGS__,,))
+#endif
+
+#if HAVE_LOCAL_ALIGNED
+#   define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_D(16, t, v, __VA_ARGS__,,))
+#else
+#   define LOCAL_ALIGNED_16(t, v, ...) E1(LOCAL_ALIGNED_A(16, t, v, __VA_ARGS__,,))
+#endif
+
+#if HAVE_LOCAL_ALIGNED
+#   define LOCAL_ALIGNED_32(t, v, ...) E1(LOCAL_ALIGNED_D(32, t, v, __VA_ARGS__,,))
+#else
+#   define LOCAL_ALIGNED_32(t, v, ...) E1(LOCAL_ALIGNED_A(32, t, v, __VA_ARGS__,,))
+#endif
+
 static inline int ff_fast_malloc(void *ptr, unsigned int *size, size_t min_size, int zero_realloc)
 {
     void *val;