[Qemu-devel] Re: [4363] MusicPal: fix gcc4 build (Jan Kiszka).

[Jan Kiszka]

Paul Brook wrote:
>> -    int16_t *codec_buffer, *mem_buffer;
>> +    int16_t *codec_buffer;
>> +    void *mem_buffer;
>> ...
>> +                mem_buffer += 2;
> 
> I really dislike doing arithmetic on a void*.

Only fair. Version below should be better (in several ways).

Index: qemu/hw/musicpal.c
===================================================================
--- qemu/hw/musicpal.c  (Revision 4365)
+++ qemu/hw/musicpal.c  (Arbeitskopie)
@@ -256,7 +256,7 @@ static void audio_callback(void *opaque,
 {
     musicpal_audio_state *s = opaque;
     int16_t *codec_buffer;
-    void *mem_buffer;
+    int8_t *mem_buffer;
     int pos, block_size;
 
     if (!(s->playback_mode & MP_AUDIO_PLAYBACK_EN))
@@ -277,8 +277,8 @@ static void audio_callback(void *opaque,
         if (s->playback_mode & MP_AUDIO_MONO) {
             codec_buffer = wm8750_dac_buffer(s->wm, block_size >> 1);
             for (pos = 0; pos < block_size; pos += 2) {
-                *codec_buffer++ = *(uint16_t *)mem_buffer;
-                *codec_buffer++ = *(uint16_t *)mem_buffer;
+                *codec_buffer++ = *(int16_t *)mem_buffer;
+                *codec_buffer++ = *(int16_t *)mem_buffer;
                 mem_buffer += 2;
             }
         } else
@@ -288,14 +288,14 @@ static void audio_callback(void *opaque,
         if (s->playback_mode & MP_AUDIO_MONO) {
             codec_buffer = wm8750_dac_buffer(s->wm, block_size);
             for (pos = 0; pos < block_size; pos++) {
-                *codec_buffer++ = cpu_to_le16(256 * *(int8_t *)mem_buffer);
-                *codec_buffer++ = cpu_to_le16(256 * *(int8_t *)mem_buffer++);
+                *codec_buffer++ = cpu_to_le16(256 * *mem_buffer);
+                *codec_buffer++ = cpu_to_le16(256 * *mem_buffer++);
             }
         } else {
             codec_buffer = wm8750_dac_buffer(s->wm, block_size >> 1);
             for (pos = 0; pos < block_size; pos += 2) {
-                *codec_buffer++ = cpu_to_le16(256 * *(int8_t *)mem_buffer++);
-                *codec_buffer++ = cpu_to_le16(256 * *(int8_t *)mem_buffer++);
+                *codec_buffer++ = cpu_to_le16(256 * *mem_buffer++);
+                *codec_buffer++ = cpu_to_le16(256 * *mem_buffer++);
             }
         }
     }