CCSv3,1 potential compiler problem

Bob Bacon

Hi Code Composer Forum
I have a customer who appears to have a potential compiler bug in CCS v3.1 (for C28xx)

I requested a much reduced dummy Code Composer project (attached) and as such does not build executable code. However, if you compile the file tb/rs485/uart_option/rs485_uart_option.c and take a look at the assembly code produced in the function received_interrupt() (a function called from an interrupt function). The instruction before the first BF instruction in this function is correct. However, if you comment out the redundant asm(" NOP") instruction in the C file, the assembly code changes and the instruction before the BF instruction is wrong:
With asm(" NOP"), the instruction before BF is MOV AH, @_g_time_overrun
With asm(" NOP") commented out, the instruction before BF is NEG AL

Is this a known problem and if so is there a workaround or will they need to update to CCSv3.3 or even v4

3666.dummy.zip

Many Thanks

Bob Bacon

over 16 years ago

0 George Mock over 16 years ago

TI__Guru**** 253300 points

I suspect this is a case of the user not using volatile correctly, but I'm not sure.

I don't have an installation of CCS v3.1 with which to build your project. And I was unable to re-create the build with that project. Please preprocess that C file as described here http://tiexpressdsp.com/index.php/Preprocess_Complex_Source_Code_for_Bug_Submissions , then post it. Also tell us the compiler version and the exact options used to create the error.

Thanks and regards,

-George

0 Bob Bacon over 16 years ago in reply to George Mock

TI__Genius 10815 points

Hi George
Here is the pre-processed code as requested

The problem is in the function receive_interrupt() on the first if-statement.
They are using Code Composer Studio V3.1.30 with code generation tools V3.11

Another Engineer at this customer claims to see a similar bug on a different part of the code, using V4.x code generation tools but I haven't managed to verify this.

6136.rs485_uart_option.zip

Thanks for your help

Bob Bacon

0 George Mock over 16 years ago in reply to Bob Bacon

TI__Guru**** 253300 points

I can reproduce the bug with v3.11. The bug does not occur when using v5.2.3 tools which come with CCSv4. The v3.11 tools are over 7 years old. Please ask your customer to update to the latest version they can. Use Update Advisor within CCS. If that doesn't work for some reason, then see http://tiexpressdsp.com/index.php/Compiler_Releases .

Thanks and regards,

-George

Code Composer Studio™︎

Code Composer Studio forum

CCSv3,1 potential compiler problem