Thread: Questions about Debug and Library

Hi,
I have two questions. Thanks in advance for helping me out!

1. This is a question of GDB. How to step over instead of stepping into in the following code:

Code:

  for(int i = 0; i < argc; i++)
    cout << (i > 0 ? "  " : "") << argv << (i < argc - 1 ? " \\" : "")
         << endl;

I try to use next to step over, but always step into some other source file as I get the information:

Code:

517      __ostream_insert(__out, __s,
(gdb)
444         { return __check_facet(_M_ctype).widen(__c); }
(gdb)
53         if (!__f)
(gdb)
873      if (_M_widen_ok)
(gdb)
1169        __tmp[__i] = __i;
(gdb)
1168      for (size_t __i = 0; __i < sizeof(_M_widen); ++__i)
(gdb)
1169        __tmp[__i] = __i;
(gdb)
1168      for (size_t __i = 0; __i < sizeof(_M_widen); ++__i)
(gdb)
1169        __tmp[__i] = __i;

If I try to step out, I get:

Code:

(gdb) finish
"finish" not meaningful in the outermost frame.

The Makefile is something like:

Code:

LDFLAGS=-static -lm -ljpeg -lpng -lz
OPTIMIZE_FLAG = -ggdb3 -DDEBUG
CXXFLAGS = -Wall $(OPTIMIZE_FLAG)
absurdity: xxx.o
    $(CXX) $(CXXFLAGS) -o $@ $^ $(LDFLAGS)
Makefile.depend: *.h *.cc Makefile
    $(CC) -M *.cc > Makefile.depend
include Makefile.depend

2. On the contrary, sometimes I'd like to get inside the implementation of some library, say libpng, but when I try to debug into it I can't. I download its source code, which contains all the .c files, from http://prdownloads.sourceforge.net/l...ar.gz?download. After ./configure, make and make install, the .h files gets into /usr/local/include/libpng12/, the library files get into /usr/local/lib/, but no .c files get into /usr/local/src/ or /usr/src. Is that why there is no source file to debug? How could I fix it?

Thanks a lot!

Thanks Mats!
I looked into the configure file. Although not completely understand it, I did ./configure debug=yes. Now I can debug into the implementation of libpng. However the source code .c files are still in the directory where I put my downloaded installation files, which means "make install" does not put .c files into some system directory like /usr/local/src or /usr/src. How to specify a directory for the source files when calling ./configure?
Thank you!

Thanks!
So it means don't delete the directory from where I built the library if debugging into the source code is desired?
I am honestly not clear about the benefit, just some intuition from previous experience that the system directory might be a relatively better place to put the source files in. If the place from where I complied the source files is Desktop or some place that I frequently clean up, then the source code will not be able to traced by debugger.

I used to program in Visual C++. If not wrong, I remember a library is usually by default installed under C:/program files/libraryname/, and header files are put under C:/program files/libraryname/include, library file under C:/program files/libraryname/lib and source files under C:/program files/libraryname/src.