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xyz2008 Author

Level 1

4 points

problem with compiling a c program

I am trying to compile a C program with the gcc command, it gives me the following error about 10 times:

warning: passing 'char *' to parameter of type 'unsigned char *' converts between

pointers to integer types with different sign [-Wpointer-sign]Pro

It does give me an executable file, but the file is not working properly. I had previously used the program on red hat and it worked fine.

Can any one help me figuring out how to make it work on my Mac. I have os X 10.9.5

Thanks!

iMac, Mac OS X (10.6.8)

Posted on Nov 18, 2015 11:48 AM

20 replies

Nov 20, 2015 6:52 AM in response to xyz2008

You might have had a PPC 10 years ago, so you might need to add a #define LINUX 1 command at the top because your program depends on the endianess of the data.

xyz2008 Author

Level 1

4 points

Nov 20, 2015 10:43 AM in response to Keith Barkley

I added the line to the program and compiled with clang, it still gives the same warnings as before during compilation. However, when I ran the newly compiled program, the output error changed. In stead of the "np" error, I get the following:

Warning: wrong status in fid 0+1 status=21725

Segmentation fault

Nov 24, 2015 11:10 AM in response to xyz2008

I don't know. it appears that your code makes too many assumptions about word size and file binary file layout, so I don't see the issue.

It would be best to create an XCode project, copy your code there and use the debugger (for example, if you were using the debugger it would tell you exactly what line is causing the segmentation fault) so you can figure out exactly what is being read into the program from the file and how to get things to work.

xyz2008 Author

Level 1

4 points

Nov 24, 2015 11:10 AM in response to Keith Barkley

Thanks!

I have never used Xcode, but thought I should give it a try. I started an Xcode project, created a .c file, copied and pasted the code into the file. Then I clicked in "run", "debugger" in the project. A new window showed up, says "debugger", but nothing happens in the debugger window, it says "no editor". And I can not paste anything into the debugger window where it says "no editor". Clearly I am not using it correctly. Would you please point me to a Xcode primer or tutorial?

xyz2008 Author

Level 1

4 points

Nov 24, 2015 11:12 AM in response to Keith Barkley

I guess the Xcode help is a good place to start?

problem with compiling a c program