Re: Profiling problem with newlib

[Jeff Johnston <jjohnstn at redhat dot com>]

On 25/11/09 02:25 PM, Joel Nygren wrote:
> Hello, I have some problems with profiling. I have compiled and
> installed newlib.
>
> cd objdir/
> ../newlib-1.17.0/configure --disable-multilib --with-newlib
> --prefix=<installdir>
> make
> make install
>
> Then I compile my programs with:
>
> /opt/gcc-4.4.1/lib/gcc -nostdlib
> <installdir>/i686-pc-linux-gnu/lib/crt0.o HelloWorld.c -I
> <installdir>/i686-pc-linux-gnu/include -L
> <installdir>/i686-pc-linux-gnu/lib -lc -lm -o Helloworld
>
> So far everything works fine. But when I add the parameter
> -fprofile-arcs to gcc, I get this error:
>
> /opt/gcc-4.4.1/lib/gcc/i686-pc-linux-gnu/4.4.1/libgcov.a(_gcov.o): In
> function `gcov_version':
> <gccSrcDir>/libgcc/../gcc/libgcov.c:141: undefined reference to `stderr'
> /opt/gcc-4.4.1/lib/gcc/i686-pc-linux-gnu/4.4.1/libgcov.a(_gcov.o): In
> function `__gcov_open':
> <gccSrcDir>/libgcc/../gcc/gcov-io.c:92: undefined reference to
> `__errno_location'
> /opt/gcc-4.4.1/lib/gcc/i686-pc-linux-gnu/4.4.1/libgcov.a(_gcov.o): In
> function `fstat':
> /usr/include/sys/stat.h:467: undefined reference to `__fxstat'
> /opt/gcc-4.4.1/lib/gcc/i686-pc-linux-gnu/4.4.1/libgcov.a(_gcov.o): In
> function `gcov_exit':
> <gccSrcDir>/libgcc/../gcc/libgcov.c:461: undefined reference to `stderr'
> <gccSrcDir>/libgcc/../gcc/libgcov.c:323: undefined reference to `stderr'
> <gccSrcDir>/libgcc/../gcc/libgcov.c:524: undefined reference to `stderr'
> /opt/gcc-4.4.1/lib/gcc/i686-pc-linux-gnu/4.4.1/libgcov.a(_gcov.o): In
> function `create_file_directory':
> <gccSrcDir>/libgcc/../gcc/libgcov.c:111: undefined reference to
> `__errno_location'
> <gccSrcDir>/libgcc/../gcc/libgcov.c:113: undefined reference to `stderr'
> /opt/gcc-4.4.1/lib/gcc/i686-pc-linux-gnu/4.4.1/libgcov.a(_gcov.o): In
> function `gcov_exit':
> <gccSrcDir>/libgcc/../gcc/libgcov.c:312: undefined reference to `stderr'
> /opt/gcc-4.4.1/lib/gcc/i686-pc-linux-gnu/4.4.1/libgcov.a(_gcov.o): In
> function `gcov_version':
> <gccSrcDir>/libgcc/../gcc/libgcov.c:141: undefined reference to `stderr'
> collect2: ld returned 1 exit status
>
> It's like libgcov.a uses libc, but libc in newlib doesn't contain these
> references. But I know that stderr is in libc, because I have used it in
> my program and it works fine. I get the same errors when I use my built
> in gcc, so I haven't done anything special with my gcc. Is there anyway
> to use fprofile-arcs with newlib?

The problem is that libgcov.a has been built using the system glibc 
headers and you are running with newlib which won't work.

You need to build your libgcov.a with newlib headers which can be done 
by putting newlib into your gcc source tree and configuring 
--with-newlib (basically link libgloss and newlib as siblings of gcc in 
the top-level src directory).  You might also need to specify 
--with-headers=xxxx where xxxx is the path to newlib's libc/include 
directory.

-- Jeff J.