Mark unreachable code on GCC even if NDEBUG

This might suppress some warnings (and very slightly reduce code size)
when assertions are disabled. Not that I particularly like to create
VLC-specific macros.

include/vlc_common.h

@@ -112,13 +112,17 @@
 
 /* Branch prediction */
 #ifdef __GNUC__
-#   define likely(p)   __builtin_expect(!!(p), 1)
-#   define unlikely(p) __builtin_expect(!!(p), 0)
+# define likely(p)     __builtin_expect(!!(p), 1)
+# define unlikely(p)   __builtin_expect(!!(p), 0)
+# define unreachable() __builtin_unreachable()
 #else
-#   define likely(p)   (!!(p))
-#   define unlikely(p) (!!(p))
+# define likely(p)     (!!(p))
+# define unlikely(p)   (!!(p))
+# define unreachable() ((void)0)
 #endif
 
+#define vlc_assert_unreachable() (assert(!"unreachable"), unreachable())
+
 /* Linkage */
 #ifdef __cplusplus
 # define VLC_EXTERN extern "C"

lib/event.c

@@ -373,7 +373,7 @@ int event_attach( libvlc_event_manager_t * p_event_manager,
     free(listener);
     fprintf( stderr, "This object event manager doesn't know about '%s' events",
              libvlc_event_type_name(event_type) );
-    assert(0);
+    vlc_assert_unreachable();
     return -1;
 }
 

modules/access/bluray.c

@@ -773,7 +773,7 @@ static int onMouseEvent(vlc_object_t *p_vout, const char *psz_var, vlc_value_t o
         bd_mouse_select(p_sys->bluray, now, val.coords.x, val.coords.y);
         bd_user_input(p_sys->bluray, now, BD_VK_MOUSE_ACTIVATE);
     } else {
-        assert(0);
+        vlc_assert_unreachable();
     }
     return VLC_SUCCESS;
 }

modules/access/dtv/en50221.c

@@ -2108,7 +2108,7 @@ void en50221_Poll( cam_t * p_cam )
     case CA_CI:
         return;
     default:
-        assert( 0 );
+        vlc_assert_unreachable();
     }
 
     for ( unsigned i_slot = 0; i_slot < p_cam->i_nb_slots; i_slot++ )

modules/access/file.c

@@ -366,7 +366,7 @@ static ssize_t StreamRead (access_t *p_access, uint8_t *p_buffer, size_t i_len)
 
 static int NoSeek (access_t *p_access, uint64_t i_pos)
 {
-    /* assert(0); ?? */
+    /* vlc_assert_unreachable(); ?? */
     (void) p_access; (void) i_pos;
     return VLC_EGENERIC;
 }

modules/access/http.c

@@ -429,7 +429,7 @@ connect:
             break;
 
         default:
-            assert(0);
+            vlc_assert_unreachable();
     }
 
     if( p_sys->i_code == 401 )

modules/access/live555.cpp

@@ -2107,7 +2107,7 @@ static void* TimeoutPrevention( void *p_data )
 
         msleep (((int64_t)p_timeout->p_sys->i_timeout - 2) * CLOCK_FREQ);
     }
-    assert(0); /* dead code */
+    vlc_assert_unreachable(); /* dead code */
 }
 
 /*****************************************************************************

modules/access/mms/mmstu.c

@@ -1573,7 +1573,7 @@ static void *KeepAliveThread( void *p_data )
 
         msleep( 10 * CLOCK_FREQ );
     }
-    assert(0);
+    vlc_assert_unreachable();
 }
 
 static void KeepAliveStart( access_t *p_access )

modules/access/v4l2/controls.c

@@ -172,7 +172,7 @@ static int ControlSetCallback (vlc_object_t *obj, const char *var,
             ret = ControlSetStr (ctrl, cur.psz_string);
             break;
         default:
-            assert (0);
+            vlc_assert_unreachable ();
     }
 
     if (ret)

modules/access/v4l2/demux.c

@@ -631,7 +631,7 @@ static void *MmapThread (void *data)
 #endif
     }
 
-    assert (0);
+    vlc_assert_unreachable ();
 }
 
 static void *ReadThread (void *data)
@@ -693,7 +693,7 @@ static void *ReadThread (void *data)
             GrabVBI (demux, sys->vbi);
 #endif
     }
-    assert (0);
+    vlc_assert_unreachable ();
 }
 
 static int DemuxControl( demux_t *demux, int query, va_list args )

modules/audio_filter/channel_mixer/remap.c

@@ -159,8 +159,7 @@ static inline uint32_t CanonicaliseChannels( uint32_t i_physical_channels )
         if( (i_physical_channels & ~valid_channels[i]) == 0 )
             return valid_channels[i];
 
-    assert( false );
-    return 0;
+    vlc_assert_unreachable();
 }
 
 /*****************************************************************************

modules/audio_output/amem.c

@@ -224,7 +224,7 @@ static int Start (audio_output_t *aout, audio_sample_format_t *fmt)
             fmt->i_physical_channels = AOUT_CHANS_7_1;
             break;
         default:
-            assert(0);
+            vlc_assert_unreachable();
     }
 
     fmt->i_format = VLC_CODEC_S16N;

modules/audio_output/audiotrack.c

@@ -611,8 +611,7 @@ JNIThread( void *data )
                                        &p_sys->p_cmd->out.time_get.i_delay );
                 break;
             default:
-                assert( false );
-                break;
+                vlc_assert_unreachable();
         }
         if( b_error )
             p_sys->b_thread_run = false;

modules/audio_output/pulse.c

@@ -430,7 +430,7 @@ static void context_cb(pa_context *ctx, pa_subscription_event_type_t type,
             break;
 
         default: /* unsubscribed facility?! */
-            assert(0);
+            vlc_assert_unreachable();
     }
 }
 

modules/codec/cc.c

@@ -479,7 +479,7 @@ static int Eia608GetWritingScreenIndex( eia608_t *h )
         return h->i_screen;
     default:
         /* It cannot happen, else it is a bug */
-        assert( 0 );
+        vlc_assert_unreachable();
         return 0;
     }
 }

modules/codec/lpcm.c

@@ -273,7 +273,7 @@ static int OpenCommon( vlc_object_t *p_this, bool b_packetizer )
             p_dec->fmt_out.i_codec = VLC_CODEC_WIDI_LPCM;
             break;
         default:
-            assert(0);
+            vlc_assert_unreachable();
         case LPCM_BD:
             p_dec->fmt_out.i_codec = VLC_CODEC_BD_LPCM;
             break;
@@ -451,7 +451,7 @@ static block_t *DecodeFrame( decoder_t *p_dec, block_t **pp_block )
             AobExtract( p_aout_buffer, p_block, i_bits, p_aob_group );
             break;
         default:
-            assert(0);
+            vlc_assert_unreachable();
         case LPCM_BD:
             BdExtract( p_aout_buffer, p_block, i_frame_length, i_channels, i_channels_padding, i_bits );
             break;
@@ -575,7 +575,7 @@ static block_t *EncodeFrames( encoder_t *p_enc, block_t *p_aout_buf )
         i_freq_code = 3;
         break;
     default:
-        assert(0);
+        vlc_assert_unreachable();
     }
 
     int i_bytes_consumed = 0;

modules/control/dbus/dbus.c

@@ -630,7 +630,7 @@ static void ProcessEvents( intf_thread_t *p_intf,
             break;
         }
         default:
-            assert(0);
+            vlc_assert_unreachable();
         }
         free( p_events[i] );
     }
@@ -1015,7 +1015,7 @@ static int AllCallback( vlc_object_t *p_this, const char *psz_var,
     else if( !strcmp( "can-pause", psz_var ) )
         info.signal = SIGNAL_CAN_PAUSE;
     else
-        assert(0);
+        vlc_assert_unreachable();
 
     if( info.signal == SIGNAL_NONE )
         return VLC_SUCCESS;

modules/control/motion.c

@@ -188,7 +188,7 @@ static void *RunIntf( void *data )
 
         vlc_restorecancel( canc );
     }
-    assert(0);
+    vlc_assert_unreachable();
 }
 #undef LOW_THRESHOLD
 #undef HIGH_THRESHOLD

modules/control/motionlib.c

@@ -194,7 +194,7 @@ static int GetOrientation( motion_sensors_t *motion )
             return 0;
 #endif
     default:
-        assert( 0 );
+        vlc_assert_unreachable();
     }
 }
 

modules/control/rc.c

@@ -1540,7 +1540,7 @@ static int VideoConfig( vlc_object_t *p_this, char const *psz_cmd,
     }
     else
         /* This case can't happen */
-        assert( 0 );
+        vlc_assert_unreachable();
 
     if( newval.psz_string && *newval.psz_string )
     {