fail to make Linux cross-compiler

[jasonlee1001]

Hi all, I want to generate elf-gcc and linux-gcc to use. elf-gcc (Newlib) is done with no errors. But fail to build "Installation (Linux)" and "Installation (Linux multilib)" with the same error messages.

 $ ./configure --prefix=/opt/riscv
 $ make linux

After very long compiling time, I got message below. Can anyone know how to fix it ? Thank you. My environment: Ubuntu 16.04, GCC version: 4.8.3

g++ -g -O2 -DIN_GCC -DCROSS_DIRECTORY_STRUCTURE -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -DHAVE_CONFIG_H -static-libstdc++ -static-libgcc -o f951 \ fortran/arith.o fortran/array.o fortran/bbt.o fortran/check.o fortran/class.o fortran/constructor.o fortran/cpp.o fortran/data.o fortran/decl.o fortran/dump-parse-tree.o fortran/error.o fortran/expr.o fortran/interface.o fortran/intrinsic.o fortran/io.o fortran/iresolve.o fortran/match.o fortran/matchexp.o fortran/misc.o fortran/module.o fortran/openmp.o fortran/options.o fortran/parse.o fortran/primary.o fortran/resolve.o fortran/scanner.o fortran/simplify.o fortran/st.o fortran/symbol.o fortran/target-memory.o fortran/convert.o fortran/dependency.o fortran/f95-lang.o fortran/trans.o fortran/trans-array.o fortran/trans-common.o fortran/trans-const.o fortran/trans-decl.o fortran/trans-expr.o fortran/trans-intrinsic.o fortran/trans-io.o fortran/trans-openmp.o fortran/trans-stmt.o fortran/trans-types.o fortran/frontend-passes.o libbackend.a main.o libcommon-target.a libcommon.a ../libcpp/libcpp.a ../libdecnumber/libdecnumber.a -lz libcommon.a ../libcpp/libcpp.a ../libbacktrace/.libs/libbacktrace.a ../libiberty/libiberty.a ../libdecnumber/libdecnumber.a attribs.o \ -lmpc -lmpfr -lgmp -rdynamic -ldl -lz fortran/arith.o: In function gfc_mpfr_to_mpz(__mpz_struct*, __mpfr_struct*, locus*)': /home/jason/work/riscv-gnu-toolchain/build-gcc-linux-stage2/gcc/../.././riscv-gcc/gcc/fortran/arith.c:51: undefined reference tompfr_get_z_exp' collect2: error: ld returned 1 exit status make[3]: [f951] Error 1 ../.././riscv-gcc/gcc/fortran/Make-lang.in:97: recipe for target 'f951' failed make[3]: Leaving directory '/home/jason/work/riscv-gnu-toolchain/build-gcc-linux-stage2/gcc' make[2]: [all-gcc] Error 2 Makefile:4316: recipe for target 'all-gcc' failed make[2]: Leaving directory '/home/jason/work/riscv-gnu-toolchain/build-gcc-linux-stage2' make[1]: [all] Error 2 Makefile:951: recipe for target 'all' failed make[1]: Leaving directory '/home/jason/work/riscv-gnu-toolchain/build-gcc-linux-stage2' make: [stamps/build-gcc-linux-stage2] Error 2 Makefile:308: recipe for target 'stamps/build-gcc-linux-stage2' failed

[jim-wilson]

This looks like a versioning problem. It appears that the mpfr version you have is either too old or too new to work with the gcc version you have. By default, we only build C and C++ for the elf compiler, but we build C, C++, and Fortran for the linux compiler, and it is the Fortran build that is failing, so only the linux compiler is failing to build.

I build on Ubuntu 16.04 often, but the gcc I have is gcc-5.4. Maybe your system hasn't been updated in a long time. If so, updating the OS may fix it. You can find the exact OS version in /etc/os-release. I have 16.04.06.

The other main alternative would be to add compatible gmp/mpc/mpfr version sources into the gcc tree. If you cd into riscv-gcc, and run "./contrib/download_prerequisties" you will get compatible versions of them downloaded which should solve the build problem.

Or you could work around the problem by disabling the Fortran support if you don't need it. In the toplevel Makefile.in look for --enable-languages=c,c++,fortran and change it to --enable-languages=c,c++ You have to do this twice.

[jasonlee1001]

Thank you very much for replying. My OS version is 16.04.06,too. I installed gcc 4.8.3 because of EDA compatible issue. I did installed gmp/mpc/mpfr manually in order to install gcc-4.8.3 successfully.

In fact, I'm currently to do the same work of this -> https://github.com/cnrv/fpga-rocket-chip In section 1.3 Preparing the Project, they said "install elf-gcc and linux-gcc and set RISCV variable in advance" , so I think it may need linux compiler.

"./contrib/download_prerequisties" , I will do this to check the required versions. Thanks again.

[jim-wilson]

Another option then would be to try doing CC=gcc-5 when configuring and making, though I don't know for sure if this will work. In theory it should force everything to use gcc-5 which is more likely to work than gcc-4.8. CC=gcc-5 configure ... CC=gcc--5 make ...

In general, the bigger the difference between the gcc versions, the more likely you are to run into problems, as new gcc versions might be using C/C++ features that old gcc versions don't support, or might trigger bugs in old gcc versions that weren't found before we stopped supporting it.

[jim-wilson]

I keep forgetting about C++. So this would have to be CC=gcc-5 CXX=g++-5 configure ... CC=gcc-5 CXX=g++-5 make ...

[dokhanchi]

Hi All, I have error on building rv32imc. I used Ubuntu 18.04 and gcc/g++ are 7.5.0.

/riscv-gnu-toolchain$ ./configure --prefix=/opt/riscv --with-arch=rv32imc checking for gcc... gcc checking whether the C compiler works... yes checking for C compiler default output file name... a.out checking for suffix of executables... checking whether we are cross compiling... no checking for suffix of object files... o checking whether we are using the GNU C compiler... yes checking whether gcc accepts -g... yes checking for gcc option to accept ISO C89... none needed checking for grep that handles long lines and -e... /bin/grep checking for fgrep... /bin/grep -F checking for grep that handles long lines and -e... (cached) /bin/grep checking for bash... /bin/bash checking for __gmpz_init in -lgmp... yes checking for mpfr_init in -lmpfr... yes checking for mpc_init2 in -lmpc... yes checking for curl... /usr/bin/curl checking for wget... /usr/bin/wget checking for ftp... /usr/bin/ftp configure: creating ./config.status config.status: creating Makefile config.status: creating scripts/wrapper/awk/awk config.status: creating scripts/wrapper/sed/sed /riscv-gnu-toolchain$ sudo make linux .... make[3]: Leaving directory '/home//SweRV/riscv-gnu-toolchain/build-gcc-linux-stage1/riscv32-unknown-linux-gnu/libgcc' make[2]: Leaving directory '/home//SweRV/riscv-gnu-toolchain/build-gcc-linux-stage1/riscv32-unknown-linux-gnu/libgcc' make[1]: Leaving directory '/home//SweRV/riscv-gnu-toolchain/build-gcc-linux-stage1' make -C build-gcc-linux-stage1 inhibit-libc=true install-target-libgcc make[1]: Entering directory '/home//SweRV/riscv-gnu-toolchain/build-gcc-linux-stage1' /bin/bash .././riscv-gcc/mkinstalldirs /opt/riscv /opt/riscv make[2]: Entering directory '/home//SweRV/riscv-gnu-toolchain/build-gcc-linux-stage1/riscv32-unknown-linux-gnu/libgcc' /bin/bash ../../.././riscv-gcc/libgcc/../mkinstalldirs /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0 /usr/bin/install -c -m 644 libgcc.a /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/ chmod 644 /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/libgcc.a /opt/riscv/riscv32-unknown-linux-gnu/bin/ranlib /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/libgcc.a /usr/bin/install -c -m 644 libgcov.a /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/ chmod 644 /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/libgcov.a /opt/riscv/riscv32-unknown-linux-gnu/bin/ranlib /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/libgcov.a parts="crtbegin.o crtbeginS.o crtbeginT.o crtend.o crtendS.o crtbegin.o crtend.o crti.o crtn.o crtendS.o crtbeginT.o"; \ for file in $parts; do \ rm -f /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/$file; \ /usr/bin/install -c -m 644 $file /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/; \ case $file in \ *.a) \ /opt/riscv/riscv32-unknown-linux-gnu/bin/ranlib ../.././gcc/$file ;; \ esac; \ done /bin/bash ../../.././riscv-gcc/libgcc/../mkinstalldirs /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/include /usr/bin/install -c -m 644 unwind.h /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/include /bin/bash ../../.././riscv-gcc/libgcc/../mkinstalldirs /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/include /usr/bin/install -c -m 644 ../../.././riscv-gcc/libgcc/gcov.h /opt/riscv/lib/gcc/riscv32-unknown-linux-gnu/9.2.0/include make[2]: Leaving directory '/home//SweRV/riscv-gnu-toolchain/build-gcc-linux-stage1/riscv32-unknown-linux-gnu/libgcc' make[1]: Leaving directory '/home//SweRV/riscv-gnu-toolchain/build-gcc-linux-stage1' mkdir -p stamps/ && touch stamps/build-gcc-linux-stage1 rm -rf stamps/build-glibc-linux-rv32imc-ilp32 build-glibc-linux-rv32imc-ilp32 mkdir build-glibc-linux-rv32imc-ilp32 cd build-glibc-linux-rv32imc-ilp32 && \ CC="riscv32-unknown-linux-gnu-gcc " \ CXX="riscv32-unknown-linux-gnu-g++ " \ CFLAGS=" -mcmodel=medlow -g -O2 " \ CXXFLAGS=" -mcmodel=medlow -g -O2 " \ ASFLAGS=" -mcmodel=medlow " \ /home//SweRV/riscv-gnu-toolchain/riscv-glibc/configure \ --host=riscv32-unknown-linux-gnu \ --prefix=/usr \ --disable-werror \ --enable-shared \ --enable-obsolete-rpc \ --with-headers=/home//SweRV/riscv-gnu-toolchain/linux-headers/include \ --disable-multilib \ --enable-kernel=3.0.0 \ \ --libdir=/usr/lib libc_cv_slibdir=/lib libc_cv_rtlddir=/lib checking build system type... x86_64-pc-linux-gnu checking host system type... riscv32-unknown-linux-gnu checking for riscv32-unknown-linux-gnu-gcc... riscv32-unknown-linux-gnu-gcc checking for suffix of object files... o checking whether we are using the GNU C compiler... yes checking whether riscv32-unknown-linux-gnu-gcc accepts -g... yes checking for gcc... gcc checking for riscv32-unknown-linux-gnu-readelf... riscv32-unknown-linux-gnu-readelf checking whether we are using the GNU C++ compiler... no checking whether riscv32-unknown-linux-gnu-g++ accepts -g... no checking whether riscv32-unknown-linux-gnu-g++ can link programs... no checking for sysdeps preconfigure fragments... aarch64 alpha arm csky hppa i386 m68k microblaze mips nios2 powerpc riscv glibc requires the A extension Makefile:238: recipe for target 'stamps/build-glibc-linux-rv32imc-ilp32' failed make: *** [stamps/build-glibc-linux-rv32imc-ilp32] Error 1

[jim-wilson]

Like the message says, riscv glibc requires the A extension. Without the A extension, you can't have any synchronization across processes, which means you can't have a multi-core multi-process multi-programmed multi-threaded OS like linux. There are probably some single process embedded real time OS ports that can work without the A extension, but not linux. On a single core single process system you can emulate atomics by disabling interrupts.

[dokhanchi]

Thank you for your help. I fixed it with: ./configure --prefix=/opt/riscv --with-arch=rv32imac

[jasonlee1001]

I reinstalled Ubuntu 16.04 on Virtual Box VM. Its default gcc version is 5.4, and it can make Linux compiler without errors. So gcc-4.8.3 seems not work to make Linux compiler. I will use Jim’s recommendation to use “CC=gcc-5 CXX=g++-5” before ./configure and make again. Thank you Jim!

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