Compiler/TMS320F28388D: How to remove errors and warning related to the helper function from run time libraries?

Be sure the source files that see diagnostics similar to ...

gurusha nahar said:

function "sqrtf" declared implicitly

... #include the RTS header file which contains the declaration of that function.  In this specific case, #include <math.h>

Please let me know if this suggestion resolves the problem.

Thanks and regards,

-George

Hi George,

Thank you for your response!

I have included this header file while creating the run time library for which, everything is linked during the library creation.

And also integrated this library in our project. When I call any of the rtl functions, for example, sqrtf(), I should not get the implicit function declaration warnings in my project, right?

Could you please explain to me why this is happening. Are we missing any linker settings?

Also, I am getting some C helper function linking issues, most of which are mention in the SPRAC71A, Table 5. Is there any rtl settings required so that these issues will be taken care while project linking.

Thanks

Gurusha

gurusha nahar said:

When I call any of the rtl functions, for example, sqrtf(), I should not get the implicit function declaration warnings in my project, right?

If you call a function, and no prototype is visible, then you will get the diagnostic about that function being declared implicitly.  This is true of both user functions and functions implemented in the compiler RTS library.

gurusha nahar said:

Are we missing any linker settings?

The diagnostic is unrelated to the linker settings.

gurusha nahar said:

Also, I am getting some C helper function linking issues, most of which are mention in the SPRAC71A, Table 5.

Please show an example of one of these issues.  Please show the full linker invocation, and all of the system response.  Please copy and paste the text, and do not use a screen shot.

Thanks and regards,

-George

Hi George,

George Mock said:

This is true of both user functions and functions implemented in the compiler RTS library.

Then include heading file again in the project, wont make it redundant. Why we need to again include the rtl header files in our project code too? Is there any alternative approach we can use.

George Mock said:

Please show an example of one of these issues. 

RIght now I have fixed those issues temporarily. But I have one concern.

I was referring compiler manual spru514v, where I saw this point mentioned in the Section 8.1 C and C++ Run-Time Support Libraries:

Compiler helper functions (to support language features that are not directly efficiently expressible in C/C++)

How this can be implemented? Are there any settings to configure the helper function?

Please help me to understand this.

Thanks

Regards

Gurusha

Gurusha,

George is out for the next week.  However I will attempt to help you with the first question.

gurusha nahar said:

George Mock

This is true of both user functions and functions implemented in the compiler RTS library.

Then include heading file again in the project, wont make it redundant. Why we need to again include the rtl header files in our project code too? Is there any alternative approach we can use.

If you are calling a function that is part of a library (any library) or even in a different source file then you need to include the header file that has the function prototype.  If you don't then you will get that implicit declaration warning at build time.  If you ever see that warning you want to stop and fix it as your program is not going to work correctly.

Here are a few links that explain this further.

https://myeasytuts.com/solved-implicit-declaration-of-function-in-c/

https://stackoverflow.com/questions/8440816/warning-implicit-declaration-of-function

https://www.quora.com/What-is-the-implicit-declaration-of-function

As far as the second question

gurusha nahar said:

I was referring compiler manual spru514v, where I saw this point mentioned in the Section 8.1 C and C++ Run-Time Support Libraries:

Compiler helper functions (to support language features that are not directly efficiently expressible in C/C++)

How this can be implemented? Are there any settings to configure the helper function?

This is similar to above.  If you want to use any of the helper functions you will have to include the appropriate header file in your source file.

Regards,

John

Oh! But initially what we assuming is if the library function call is already linked with the application, then we shouldn't be getting this warning.

But since you confirm it, then we will be including again the header file wherever we are calling the library function. 

Also

JohnS said:

This is similar to above.  If you want to use any of the helper functions you will have to include the appropriate header file in your source file.

NO, this is not the case!

If you see the helper functions, mostly are the part of some asm file. We cannot include almost all the asm files in our RTL.

There is for sure, some missing part in our RTL.

As George knows our status, he could be able to help us!

What I will do is attach the dummy project for which I am getting the helper function error.

Kindly please check the issue and let us know what we are exactly missing here.

If you build the dummy project, you will also get that linker error.

Hope it will help you to understand my doubt!.

Dummy_Proj.zip

Thanks

Regards

Gurusha

To use logf() then include math.h

You will also have to add the necessary path to the include search path here:

I added ${CG_TOOL_ROOT}/include instead of using an absolute path.  ${CG_TOOL_ROOT} is resolved to the location where the compiler is installed and math.h is located in the /include folder under that.

Regards,

John

Hi,

The intend for sharing this project is to show you the linker issues I am getting. For this project, we can resolve it by inserting the header file. But for our project when we tried in the same way but still getting the compilation issue. I am trying creating the same scenario. I will post the exact issue. My only concern is the statement in sprac71a.  In section 6.2, on page no.31 it states :

"The compiler generates calls to helper functions to perform operations that need to be supported by the compiler, but are not supported directly by the architecture, such as floating-point operations on devices that lack dedicated hardware. These helper functions must be implemented in the RTS library of any toolchain that conforms to the ABI"

Gurusha,

George will be back on Monday and can respond then.

Regards,

John