Don't allocate pulses on the stack when calling the SILK PLC.

Also minor C89 fix for the previous commit

celt/celt_decoder.c

@@ -406,8 +406,8 @@ static void tf_decode(int start, int end, int isTransient, int *tf_res, int LM,
 static int celt_plc_pitch_search(celt_sig *decode_mem[2], int C, int arch)
 {
    int pitch_index;
-   SAVE_STACK;
    VARDECL( opus_val16, lp_pitch_buf );
+   SAVE_STACK;
    ALLOC( lp_pitch_buf, DECODE_BUFFER_SIZE>>1, opus_val16 );
    pitch_downsample(decode_mem, lp_pitch_buf,
          DECODE_BUFFER_SIZE, C, arch);

silk/decode_frame.c

@@ -47,13 +47,10 @@ opus_int silk_decode_frame(
 {
     VARDECL( silk_decoder_control, psDecCtrl );
     opus_int         L, mv_len, ret = 0;
-    VARDECL( opus_int16, pulses );
     SAVE_STACK;
 
     L = psDec->frame_length;
     ALLOC( psDecCtrl, 1, silk_decoder_control );
-    ALLOC( pulses, (L + SHELL_CODEC_FRAME_LENGTH - 1) &
-                   ~(SHELL_CODEC_FRAME_LENGTH - 1), opus_int16 );
     psDecCtrl->LTP_scale_Q14 = 0;
 
     /* Safety checks */
@@ -62,6 +59,9 @@ opus_int silk_decode_frame(
     if(   lostFlag == FLAG_DECODE_NORMAL ||
         ( lostFlag == FLAG_DECODE_LBRR && psDec->LBRR_flags[ psDec->nFramesDecoded ] == 1 ) )
     {
+        VARDECL( opus_int16, pulses );
+        ALLOC( pulses, (L + SHELL_CODEC_FRAME_LENGTH - 1) &
+                       ~(SHELL_CODEC_FRAME_LENGTH - 1), opus_int16 );
         /*********************************************/
         /* Decode quantization indices of side info  */
         /*********************************************/