FreeRTOS V3.0 PIC18 port withe mcc18

nobody wrote on Sunday, June 05, 2005:

Hi everybody,
I’m new at Freertos and I wanted to try it. I’m using mplab and a custom board with an PIC18f452. My first compile with mcc18 fails with the following error : Executing: “I:\mcc18\bin\mcc18.exe” -p=18F452 “tasks.c” -fo=“tasks.o” /i"I:\mcc18\h" /i"M:\FreeRTOS\demo\common\include" /i"M:\FreeRTOS\source\include" /i"M:\FreeRTOS\source\portable\mplab\PIC18F" /i"M:\FreeRTOS\demo\PIC18_MPLAB" -w3 -DMPLAB_PIC18F_PORT -Ls -Opa-
M:\FreeRTOS\Source\tasks.c:176:Fatal [100] -internal- unhandled opcode in constant expression
Error executing I:\mcc18\bin\mcc18-traditional [error=1]
Halting build on first failure as requested.

The source line concerned in tasks.c is as follows :
static volatile xListpxReadyTasksLists[configMAX_PRIORITIES];    /*< Prioratised ready tasks. */
If someone has already faced the same problem or any idea please help.
thanks in advance.

rtel wrote on Sunday, June 05, 2005:

Does the code compile exactly as downloaded (without modification).

If you get the same problem with the unmodified code then this could be an MPLAB C problem.  I have found the following extract from a MPLAB bug list:

"(20361) the ‘sizeof’ operator when used to specify an array size may
  cause an internal error:

     char buf[sizeof("hello world")];   

   Fatal [100]-internal - unhandled opcode in constant expression

   The workaround is to use a different method of specifying the array size

     #define STRING_LEN 11
     char buf[STRING_LEN + 1];

The sizeof operator is not explicitly used to define configMAX_PRIORITIES but may be used implicitly because of the cast.

configMAX_PRIORITIES is defined in FreeRTOS\Demo\PIC18_MPLAB\FreeRTOSConfig.h.  Try removing the cast in the constant definition so it reads:

#define configMAX_PRIORITIES       4

Which version of the compiler and IDE are you using?