BL51: WARNING L16 (UNCALLED SEGMENT) ?C_INITSEG

Information in this article applies to:

• C51 All Versions

QUESTION

I have written my own startup sequence, but now I keep getting the following linker warning:

*** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS
    SEGMENT: ?C_INITSEG

What is the problem?

ANSWER

The uncalled segment, ?C_INITSEG, is the name given to the global variable initialization code. This segment is automatically included when a program with initialized global or static variables. For example:

int i = 5;   // this generates an INITSEG table entry

int test (void)  {
  return (i);
}

RAM variable initializations generate table entries in the ?C_INITSEG segment. ?C_INITSEG is called at the end of the startup code to initialize global variables. Then, the main C function is invoked.

It seems that the ?C_INITSEG segment was included in the program linkage but was never invoked. There are several ways to solve this problem:

1. If you use modified STARTUP code, make sure that you call ?C_START at the end of the CPU initialization. This executes the function that reads the ?C_INITSEG and then calls main. Source code for this function is provided in the file INIT.A51.
2. You may use a separate function that initializes all your variables. For example:

   void init (void)  {
     i = 5;
   }
   

MORE INFORMATION

• Refer to Warning L16 in the BL51 User's Guide.
• Refer to Warning L16 in the LX51 User's Guide.

SEE ALSO

• C51: PURPOSE OF THE INIT.A51 FILE
• C51: WHEN/WHERE ARE GLOBAL AND STATIC VARIABLES INITIALIZED?
• C51: GLOBAL OR STATIC VARIABLES NOT BEING INITIALIZED
• C51: CONTENTS OF THE ?C_INITSEG SEGMENT

FORUM THREADS

The following Discussion Forum threads may provide information related to this topic.

• uncalled segment ignored for overlay segment?c_initseg
• hex file generation
• c_initseg

Last Reviewed: Friday, November 16, 2007