[Bug other/116119] Error building gcc 8.3.0

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116119

--- Comment #12 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I can build fine using these steps:

  export TARGET=arm-linux-gnueabihf
  export PREFIX=/tmp/rpi-toolchain
  wget https://ftp.gnu.org/gnu/binutils/binutils-2.31.tar.gz
  tar xf binutils-2.31.tar.gz 
  cd bobj
  ../binutils-2.31/configure --target=${TARGET} --prefix=${PREFIX}
--with-arch=armv8-a --with-fpu=vfp --with-float=hard --disable-multilib
  make -j10 && make install
  cd ../
  ~/src/gcc/gcc-8/configure --prefix=${PREFIX} --target=${TARGET} 
--enable-languages=c,c++ --disable-multilib --enable-multiarch
--with-arch=armv8-a --with-fpu=vfp --with-float=hard
  make all-gcc -j10 

Where ~/src/gcc/gcc-8 contains the gcc-8.5.0 sources and gmp, mpfr and mpc
sources.

I don't have a sysroot, so I can't build libgcc and the rest of the compiler,
but I don't get an error from configure-gmp like in comment 7. My build gets
past that without problems. So you must be doing something differently.

Start again. Remove the entire working directory that you're building in, as
it's clearly messed up (see comment 11, with the error taken from the logs in
comment 6).

Build and install binutils first.
Use contrib/download_prerequisites after un-tarring the gcc sources.
Build and install gcc.

Don't reconfigure in the same directory where you've already got a failed build
using a different configuration. Don't mess with LD_LIBRARY_PATH.
Use gcc-8.5.0 not 8.3.0 because it has various bugs fixed (probably nothing
relevant to your problem, it's just a better release).

The instructions you're following seem broken:

cd ~/rpi0/toolchain/sources/gcc-8.3.0
contrib/download_prerequisites
mkdir -p ../../build/gcc2
pushd build/gcc2
      ^^^^^^^^^^ that's not the directory that was just created, should be
../../

../../src/gcc-8.3.0/configure
      ^^^ that's not where the sources are, should be sources not src