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Combuster wrote:I'd still file the bug for the sake of it.

Solar wrote:Personally, I'd suggest scrapping the "installing from source" part for GMP, MPFR and MPC (which aren't cross-compile specific anyway), and instead recommend installing the appropriate packages (e.g. libmpc-devel) through the respective system package manager. That way, cross-binutils and cross-GCC can be installed anywhere you like, and you don't even have to state --with-gmp etc. during config.

Solar wrote:Transferring this from the Wiki discussion page...

GCC 4.5.0 introduces a new dependency, the MPC library, which isn't covered by the tutorial yet. But that isn't my problem.

It seems that the tutorial only works when you use /usr/local as the prefix.

During the configure step for GCC, you state --with-gmp=..., --with-mpfr=... and --with-mpc=..., which allows the build process to find the headers and linker libraries. Unfortunately the search path for the libraries does not get coded into the resulting executables:

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/usr/src/build-gcc/gcc $ ldd cc1
	linux-gate.so.1 =>  (0xb804e000)
	libmpc.so.2 => not found
	libmpfr.so.1 => /usr/lib/libmpfr.so.1 (0xb7fed000)
	libgmp.so.10 => not found
	libdl.so.2 => /lib/tls/i686/cmov/libdl.so.2 (0xb7fe8000)
	libc.so.6 => /lib/tls/i686/cmov/libc.so.6 (0xb7e85000)
	libgmp.so.3 => /usr/lib/libgmp.so.3 (0xb7e3e000)
	/lib/ld-linux.so.2 (0xb804f000)

Not only does cc1 not find the libmpc.so.2 despite being told it resides in /usr/cross/lib during the configure, it also links the system-provided gmp / mpfr libraries in /usr/lib despite being told to use those in /usr/cross/lib.

I really despise this kind of autoconfig stupidity.

I don't like mixing manually-installed libraries with the code under control of my system package manager, and anyway by using $PREFIX our tutorial gives the impression of being independent of the actual location binaries are installed to - which obviously it is not.

And editing /etc/ld.so.conf isn't an option for people who are working as non-root on shared systems.

I'd really like to file this as a bug in GCC / Autoconfig, but I know what the answer would be.

How do we handle this in the tutorial? Hardcode /usr/local and scrap $PREFIX, recommend editing /etc/ld.so.conf (which would be tricky since distros differ in this regard), or something else? (Please nobody recommend setting LD_LIBRARY_PATH, that's evil.)

It's a hack but to help GCC find the libraries you can create the LD_LIBRARY_PATH for example

--with-gmp
--with-mpfr
--with-mpc

pcmattman wrote:

It's a hack but to help GCC find the libraries you can create the LD_LIBRARY_PATH for example

It's not a hack but to help GCC find the libraries you can use:

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--with-gmp
--with-mpfr
--with-mpc

Install GMP, MPFR and MPC in one root, say, /usr, and then pass "--with-gmp=/usr" to configure and it will find the rest.

configure will probe <with_gmp_path>/lib and <with_gmp_path>/include for all three dependencies - if you have separate directories for each you'll need all three options.

There's absolutely no need to fiddle with environment variables in this tutorial, apart from adding $PREFIX/bin to $PATH (which is only necessary if you want to run the output after building it).