Re: Linking troubles with gcc 4.5

[Andrew Haley <aph at redhat dot com>]

On 05/26/2010 07:43 PM, lfrfly@icqmail.com wrote:
> Reply below....
> 
> On 05/26/2010 05:50 PM, lfrfly@icqmail.com wrote:
>>  I recently built gcc 4.5 from source. That took a bit of doing, but
>> eventually I got to working. Since I don't have admin on this 
> machine, I
>> set the --prefix to /u1/public/gcc and make installed it there.
>>
>> I am now able to compile with g++ 4.5. To help, I did
>> alias g++0x /u1/public/gcc/bin/g++ -std=c++0x
>>
>> However, linking doesn't yet work. I got:
>> /usr/bin/ld: cannot find -lgcc_s
>> And when I changed the alias to include
>> -L/u1/public/gcc/lib/gcc/x86_64-unknown-linux-gnu/4.5.0/
>> -L/u1/public/gcc/lib/gcc/x86_64-unknown-linux-gnu/lib/
>> then I got
>> /usr/bin/ld: skipping incompatible
>> /u1/public/gcc/lib/gcc/x86_64-unknown-linux-gnu/lib//libgcc_s.so when
>> searching for -lgcc_s
>> /usr/bin/ld: cannot find -lgcc_s
>>
>> Any ideas?
> 
> You haven't given us a huge amount of information: usually we'd
> want the configure line and the command you use to do the test.
> 
> However, you can use "strace -etrace-file" to see where g++ is looking
> for libgcc_s.so.  That'll give you a clue.
> 
> Andrew.
> 
> 
> *************
> 
> Well, I've attached the strace output. I'm not sure if it'll be much
> help; the only suspicious thing I see is that it's trying to access
> /usr/lib at one point, and there could be files used by gcc 4.1 in there.

Ahhh, "strace -f -etrace-file".  And the output is for you to read.  :-)

> As far as the configure line,
> [***]$ g++0x -v
> Using built-in specs.
> COLLECT_GCC=/u1/public/gcc/bin/g++
> COLLECT_LTO_WRAPPER=/u1/public/gcc/libexec/gcc/x86_64-unknown-linux-gnu/4
> .5.0/lto-wrapper
> Target: x86_64-unknown-linux-gnu
> Configured with: ../gcc-4.5.0/configure --prefix=/u1/public/gcc
> --enable-shared --enable-threads=posix --enable-__cxa_atexit
> --enable-version-specific-runtime-libs
> Thread model: posix
> gcc version 4.5.0 (GCC)

Hmm, this isn't a Debian-derived distro, is it?  They sometimes put
the libraries in the wrong place.

Andrew.