[Tinyos-help] a strange error

[Murray, Ben]

That is a pretty common, and standard C error.
You cannot perform an operation prior to declaring a variable (...or: you
cannot declare a variable /after/ an operation has been performed)

In this case the function start is the  open-brace of the else command:
begin-brace	> 	  else {
operation	> 	    Counter++; 
declaration	> 	    radio_test_msg_t* rcm =
(radio_test_msg_t*)call...
produces an error as it is "not allowed".

If you want it there you either declare rcm at the start of the .fired()
event or you put the counter++ operation /after/ the rcm declaration:
begin-brace	> 	  else {
declaration	> 	    radio_test_msg_t* rcm =
(radio_test_msg_t*)call...
operation	> 	    Counter++; 
should work fine.

Cheers
-Ben


> -----Original Message-----
> From: tinyos-help-bounces at millennium.berkeley.edu
> [mailto:tinyos-help-bounces at millennium.berkeley.edu]On Behalf 
> Of weiping
> SONG
> Sent: 11 March 2008 12:33
> To: tinyos-help at millennium.berkeley.edu
> Subject: [Tinyos-help] a strange error 
> 
> 
> Hi all,
> 
> I faced a strange error  this morning as following:
> I could not compile my TestRadioAppC.nc if I put "Counter++;" before 
> radio_test_mag_t in TestRadioC.nc...
> 
> ---------------------------------------------------------------------
> event void TimerRadio.fired() {
> 	 // Counter++;
> 	  if (locked) {
> 	    return;
> 	  }
> 	  else {
> 	    Counter++;
> 	    radio_test_msg_t* rcm = (radio_test_msg_t*)call 
> Packet.getPayload(&packet, NULL);
> 	    if (call Packet.maxPayloadLength() < 
> sizeof(radio_test_msg_t)) {
> 	      return;
> 	    }
> 
> 	    rcm->voltage = InVoltage;
> 	    rcm->count = Counter;
> 	    rcm->temp = 0;
> 	    if (call AMSend.send(AM_BROADCAST_ADDR, &packet, 
> sizeof(radio_test_msg_t)) == SUCCESS) {
> 		 locked = TRUE;
> 	    }
> 	  }
> 	}
> --------------------------------------------------------------
> --------------------------------------------
> [realtime at m1-02 TestRadio]$ make telosb
> mkdir -p build/telosb
>     compiling TestRadioAppC to a telosb binary
> ncc -o build/telosb/main.exe -Os -O -mdisable-hwmul -Wall 
> -Wshadow -DDEF_TOS_AM_GROUP=0x7d -Wnesc-all -target=telosb 
> -fnesc-cfile=build/telosb/app.c -board= 
> -DIDENT_PROGRAM_NAME=\"TestRadioAppC\" 
> -DIDENT_USER_ID=\"realtime\" 
> -DIDENT_HOSTNAME=\"m1-02.ucc.ie\" 
> -DIDENT_USER_HASH=0x69427c28L -DIDENT_UNIX_TIME=0x47d67976L 
> -DIDENT_UID_HASH=0xc8fd72abL  TestRadioAppC.nc -lm
> In file included from TestRadioAppC.nc:13:
> In component `TestRadioC':
> TestRadioC.nc: In function `TimerRadio.fired':
> TestRadioC.nc:47: syntax error before `*'
> TestRadioC.nc:52: `rcm' undeclared (first use in this function)
> TestRadioC.nc:52: (Each undeclared identifier is reported only once
> TestRadioC.nc:52: for each function it appears in.)
> make: *** [exe0] Error 1
> [realtime at m1-02 TestRadio]$
> 
> --------------------------------------------------------------
> --------------------------------------------------------------------
> 
> But it worked well if I put "Counter++;" in the first line of 
> the event.
> 
> I do not understand why, can some one help me?
> 
> Regards,
> 
> Weiping Song
> _______________________________________________
> Tinyos-help mailing list
> Tinyos-help at millennium.berkeley.edu
> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/t
inyos-help

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