Compiler/TMS320F28335: Compilation errors of redefined stido.h functions after removing extern "C" from header files

I'm confused.  Are you modifying compiler RTS header files like stdio.h?  That is not supported.  For now, I presume you only modify your own source files.

Please pick one problem source file and make a test case out of it as described in How to Submit a Compiler Test Case.  But please submit one more file.  Also build the same file with the option --gen_preprocessor_listing.  This creates a listing file with the extension .rl.  Add the file extension .txt to it, and also attach it to your next forum post.

Thanks and regards,

-George

I'm confused.  Are you modifying compiler RTS header files like stdio.h?  That is not supported.  For now, I presume you only modify your own source files.

Nope, I am only changing the files in the project folder. stdio.h is contained in the compiler folder.

Please pick one problem source file and make a test case out of it as described in How to Submit a Compiler Test Case.  But please submit one more file.  Also build the same file with the option --gen_preprocessor_listing.  This creates a listing file with the extension .rl.  Add the file extension .txt to it, and also attach it to your next forum post.

I don't have access to the code at this time, so I created a test project that highlights the issue.  While creating the test project, I realized I needed to use  "using namespace std" to get rid of some of the compiler errors.  I am not sure why the compiler is now able to to find sscanf().

Please see attached test project.  

TestProject1.zip

Stephen

Ok, that clears up the confusion a lot. I'll try it once I get back to my desk and get back with you on what I finally decided to do.

Thanks,
Stephen

You are definitely correct about the hefty library cost. The simple program shown below took up a total of 90930 words of memory, with 79900 of it in the text section.

Back to my issue:

fgetc() and fputc() are calling c++ driver functions.  When I compile the file containing fgetc and fputs, the compiler complains that it can't find the c++ driver function.

I am not putting the c++ driver header file inside the extern "C" declaration, so the fgetc and fputc functions should be calling the name mangled c++ driver functions. 

What am I doing wrong?

Stephen

#include <iostream>


int main(void) {
	
	return 0;
}

The normal fgetc and fputc functions do not call any C++ functions. They call C functions, all the way down to the CIO interface.  Your replacement functions should not call any C++ functions, either.

You said that "the compiler complains that it can't find the c++ driver function." What is the name of that function? What is the exact text of the error from the compiler?

You need two files, main.cpp and myfputs.c, like so:

/* main.cpp */
#include <stdio.h>

int main()
{
   fputs("I am a call to fputs");
}

Notice that because I've included stdio.h, I can call fputs without using std::

/* myfputs.c */
#include <stdio.h>

int fputs(const char *s, FILE *stream)
{
     /* your implementation */
}

Notice that because this is a C file, I just include stdio.h and I get the correct prototype for fputs.

Do not include <iostream> unless you want to use std::cout. It does not change the program in any way but to allow you to use std::cout.  If you want to use any of the C output functions (e.g. printf, puts, putchar), include either stdio.h, or cstdio