Compiling gcc-7.2.0 - Githubissues

FelixVi commented 6 years ago

When compiling gcc-7.2.0, libquadmath was causing an error.

Not sure if there's anything more behind this, but I got past the problem by changing step 4 in the readme from

4. Compile and install GCC. Take gcc-core and gcc-g++ from GNU
   (version 4.5 or >=4.9).
   rm -rf libstdc++-v3
   mkdir build && cd build
   ../configure --target=lm32-elf --enable-languages="c,c++" --disable-libgcc \
     --disable-libssp
   make
   make install

to

4. Compile and install GCC. Take gcc-core and gcc-g++ from GNU
   (version 4.5 or >=4.9).
   rm -rf libstdc++-v3
   mkdir build && cd build
   ../configure --target=lm32-elf --enable-languages="c,c++" --disable-libgcc \
     --disable-libssp --disable-libquadmath
   make
   make install

If this is a good fix, an update in the readme might be a good thing.

sbourdeauducq commented 6 years ago

Should be fine. Though I'd be surprised if new gcc still works for lm32 without other bugs, so make sure working versions still can be compiled, e.g. are happy with that quadmath flag.

sbourdeauducq commented 6 years ago

Or check 7.2 thoroughly...

FelixVi commented 6 years ago

So far, I have not noticed any issues with 7.2, but to be safe I'll downgrade to version 4.9. Thanks!

mithro commented 6 years ago

We have been actively using GCC 5.4 on the HDMI2USB project with the lm32 and it has been working fine - our conda packages are here -> https://github.com/timvideos/conda-hdmi2usb-packages/blob/master/lm32/gcc-nostdc/meta.yaml

  fn: gcc-5.4.0.tar.bz2
  url: ftp://ftp.gnu.org/gnu/gcc/gcc-5.4.0/gcc-5.4.0.tar.bz2
  sha256: 608df76dec2d34de6558249d8af4cbee21eceddbcb580d666f7a5a583ca3303a

We don't however do anything advanced in our firmware code, so might not be hitting broken code paths. Do you know if there is a regression suite we can use to test if the lm32 is working correctly?

sbourdeauducq commented 6 years ago

Doesn't GCC come with one?

m-labs / misoc

Compiling gcc-7.2.0 #61