Summary: Error message:

    lto1: internal compiler error: in input_overwrite_node, at lto-cgraph.c:1203
On GCC 6.1.0

Compiling this code:

    void test()
    {
    }
    int main()
    {
      #pragma acc parallel
      test();
    }

With this commandline:

    gcc tmpe.c  -O0 -fopenacc -v

Complete output of GCC:

    Using built-in specs.
    COLLECT_GCC=/usr/local/bin/gcc
    COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0/lto-wrapper
    OFFLOAD_TARGET_NAMES=nvptx-none
    Target: x86_64-pc-linux-gnu
    Configured with: ../configure --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=x86_64-pc-linux-gnu --enable-offload-targets=nvptx-none=/usr/local/nvptx-none --enable-languages=c,c++ --with-cuda-driver=/usr --disable-bootstrap
    Thread model: posix
    gcc version 6.1.0 (GCC) 
    COLLECT_GCC_OPTIONS='-O0' '-fopenacc' '-v' '-mtune=generic' '-march=x86-64' '-pthread'
     /usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0/cc1 -quiet -v -imultiarch x86_64-linux-gnu -D_REENTRANT tmpe.c -quiet -dumpbase tmpe.c -mtune=generic -march=x86-64 -auxbase tmpe -O0 -version -fopenacc -o /tmp/ccPHnCW0.s
    GNU C11 (GCC) version 6.1.0 (x86_64-pc-linux-gnu)
    	compiled by GNU C version 6.1.0, GMP version 6.0.0, MPFR version 3.1.4, MPC version 1.0.3, isl version 0.15
    GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
    ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
    ignoring nonexistent directory "/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../x86_64-pc-linux-gnu/include"
    #include "..." search starts here:
    #include <...> search starts here:
     /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/include
     /usr/local/include
     /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/include-fixed
     /usr/include/x86_64-linux-gnu
     /usr/include
    End of search list.
    GNU C11 (GCC) version 6.1.0 (x86_64-pc-linux-gnu)
    	compiled by GNU C version 6.1.0, GMP version 6.0.0, MPFR version 3.1.4, MPC version 1.0.3, isl version 0.15
    GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
    Compiler executable checksum: 1c46fde4e47f1157bf1461541c266a3c
    COLLECT_GCC_OPTIONS='-O0' '-fopenacc' '-v' '-mtune=generic' '-march=x86-64' '-pthread'
     as -v --64 -o /tmp/ccd60m4w.o /tmp/ccPHnCW0.s
    GNU assembler version 2.26 (x86_64-linux-gnu) using BFD version (GNU Binutils for Debian) 2.26
    COMPILER_PATH=/usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0/:/usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0/:/usr/local/libexec/gcc/x86_64-pc-linux-gnu/:/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/:/usr/local/lib/gcc/x86_64-pc-linux-gnu/
    LIBRARY_PATH=/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/:/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/:/lib/x86_64-linux-gnu/:/lib/../lib64/:/usr/lib/x86_64-linux-gnu/:/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../:/lib/:/usr/lib/
    Reading specs from /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64/libgomp.spec
    COLLECT_GCC_OPTIONS='-O0' '-fopenacc' '-v' '-mtune=generic' '-march=x86-64' '-pthread'
     /usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0/collect2 -plugin /usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0/liblto_plugin.so -plugin-opt=/usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0/lto-wrapper -plugin-opt=-fresolution=/tmp/ccPr7Oc3.res -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lpthread -plugin-opt=-pass-through=-lc -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lgcc_s --eh-frame-hdr -m elf_x86_64 -dynamic-linker /lib64/ld-linux-x86-64.so.2 /usr/lib/x86_64-linux-gnu/crt1.o /usr/lib/x86_64-linux-gnu/crti.o /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtbegin.o /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtoffloadbegin.o -L/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0 -L/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../../../lib64 -L/lib/x86_64-linux-gnu -L/lib/../lib64 -L/usr/lib/x86_64-linux-gnu -L/usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/../../.. /tmp/ccd60m4w.o -lgomp -lgcc --as-needed -lgcc_s --no-as-needed -lpthread -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtend.o /usr/lib/x86_64-linux-gnu/crtn.o /usr/local/lib/gcc/x86_64-pc-linux-gnu/6.1.0/crtoffloadend.o
    /usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0//accel/nvptx-none/mkoffload @/tmp/ccDURU7y
    /usr/local/bin/x86_64-pc-linux-gnu-accel-nvptx-none-gcc @/tmp/cchbn3g5
    Using built-in specs.
    COLLECT_GCC=/usr/local/bin/x86_64-pc-linux-gnu-accel-nvptx-none-gcc
    COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0/accel/nvptx-none/lto-wrapper
    Target: nvptx-none
    Configured with: ../configure --target=nvptx-none --enable-as-accelerator-for=x86_64-pc-linux-gnu --disable-sjlj-exceptions --enable-newlib-io-long-long --enable-languages=c,c++ --with-build-time-tools=/usr/local/nvptx-none/bin : (reconfigured) ../configure --target=nvptx-none --enable-as-accelerator-for=x86_64-pc-linux-gnu --disable-sjlj-exceptions --enable-newlib-io-long-long --enable-languages=c,c++ --with-build-time-tools=/usr/local/nvptx-none/bin
    Thread model: single
    gcc version 6.1.0 (GCC) 
    COLLECT_GCC_OPTIONS='-v' '-m64' '-v' '-fmath-errno' '-fsigned-zeros' '-ftrapping-math' '-fno-trapv' '-fno-strict-overflow' '-fno-openmp' '-foffload-abi=lp64' '-O0' '-fopenacc' '-o' '/tmp/ccbsSD6y.mkoffload'
     /usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0/accel/nvptx-none/lto1 -quiet -dumpbase ccd60m4w.o -m64 -auxbase ccd60m4w -O0 -version -fmath-errno -fsigned-zeros -ftrapping-math -fno-trapv -fno-strict-overflow -fno-openmp -foffload-abi=lp64 -fopenacc @/tmp/ccBVSiU2 -o /tmp/ccSbKQ4y.s
    GNU GIMPLE (GCC) version 6.1.0 (nvptx-none)
    	compiled by GNU C version 4.9.2, GMP version 6.0.0, MPFR version 3.1.4, MPC version 1.0.3, isl version 0.15
    GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
    GNU GIMPLE (GCC) version 6.1.0 (nvptx-none)
    	compiled by GNU C version 4.9.2, GMP version 6.0.0, MPFR version 3.1.4, MPC version 1.0.3, isl version 0.15
    GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
    lto1: internal compiler error: in input_overwrite_node, at lto-cgraph.c:1203
    0x7984cd input_overwrite_node
    	../../gcc/lto-cgraph.c:1201
    0x7984cd input_node
    	../../gcc/lto-cgraph.c:1296
    0x7984cd input_cgraph_1
    	../../gcc/lto-cgraph.c:1546
    0x7984cd input_symtab()
    	../../gcc/lto-cgraph.c:1849
    0x53e23f read_cgraph_and_symbols
    	../../gcc/lto/lto.c:2856
    0x53e23f lto_main()
    	../../gcc/lto/lto.c:3304
    Please submit a full bug report,
    with preprocessed source if appropriate.
    Please include the complete backtrace with any bug report.
    See <http://gcc.gnu.org/bugs.html> for instructions.
    mkoffload: fatal error: /usr/local/bin/x86_64-pc-linux-gnu-accel-nvptx-none-gcc returned 1 exit status
    compilation terminated.
    lto-wrapper: fatal error: /usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0//accel/nvptx-none/mkoffload returned 1 exit status
    compilation terminated.
    /usr/bin/ld: error: lto-wrapper failed
    collect2: error: ld returned 1 exit status

Operating system: Debian Jessie on x86_64.

GCC was installed using the following sequence of commands, after instructions from https://gcc.gnu.org/wiki/Offloading:

        apt-get install -t jessie-backports nvidia-cuda-toolkit libcuda1:i386 build-essential git gcc-multilib
        apt-get install -t binutils/testing binutils-multiarch/testing
        cd /usr/local/src
                git clone https://github.com/MentorEmbedded/nvptx-tools
                cd nvptx-tools
                ./configure; make -j8; make install
        cd /usr/local/src
                git clone https://github.com/MentorEmbedded/nvptx-newlib
        cd /dev/shm
                wget ftp://ftp.uvsq.fr/pub/gcc/releases/gcc-6.1.0/gcc-6.1.0.tar.bz2
                tar xvfj gcc-6.1.0.tar.bz2
                cd gcc-6.1.0
                mkdir build ; cd build
                ln /usr/local/src/nvptx-newlib/newlib -s ../newlib
                ../configure --target=nvptx-none --enable-as-accelerator-for=x86_64-pc-linux-gnu \
                        --disable-sjlj-exceptions --enable-newlib-io-long-long \
                        --enable-languages=c,c++ --with-build-time-tools=/usr/local/nvptx-none/bin
                make -j8 ; make install
                rm -rf *
                ../configure --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu \
                        --target=x86_64-pc-linux-gnu \
                        --enable-offload-targets=nvptx-none=/usr/local/nvptx-none \
                        --enable-languages=c,c++ \
                        --with-cuda-driver=/usr \
                        --disable-bootstrap
                make -j8 ; make install

The exact same error was also reproduced when --disable-bootstrap was not used.

For reference, the problems seems to be in the transfer of code from the host compiler to the nvptx cross compiler. These individual commands run successfully:

    x86_64-pc-linux-gnu-accel-nvptx-none-gcc tmpe.c -S -o-
    gcc tmpe.c  -O0 -fopenacc -c

But if I run the host GCC separately like that, I get a different ICE from mkoffload:

    COLLECT_GCC=x86_64-pc-linux-gnu-accel-nvptx-none-gcc \
    /usr/local/libexec/gcc/x86_64-pc-linux-gnu/6.1.0//accel/nvptx-none/mkoffload tmpe.o
    mkoffload: internal compiler error: in main, at config/nvptx/mkoffload.c:502
    Please submit a full bug report,
    with preprocessed source if appropriate.
    Please include the complete backtrace with any bug report.
    See <http://gcc.gnu.org/bugs.html> for instructions.