https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66942
--- Comment #4 from Vittorio Zecca <zeccav at gmail dot com> --- Did you put the gcc_assert line in the source? If you have not a sanitized version you will not see the null pointer dereferencing Anyway this is what you asked me: (please not the runtime error: sanitizer messages) ~/local/gcc-5.2.0-sanitized/bin/gfortran -v -S gfbug120.f Using built-in specs. COLLECT_GCC=/home/vitti/local/gcc-5.2.0-sanitized/bin/gfortran Target: x86_64-unknown-linux-gnu Configured with: ../gcc-5.2.0/configure --prefix=/home/vitti/local/gcc-5.2.0-sanitized --disable-bootstrap --enable-languages=c,c++,fortran --disable-lto Thread model: posix gcc version 5.2.0 (GCC) COLLECT_GCC_OPTIONS='-v' '-S' '-mtune=generic' '-march=x86-64' /home/vitti/local/gcc-5.2.0-sanitized/libexec/gcc/x86_64-unknown-linux-gnu/5.2.0/f951 gfbug120.f -ffixed-form -quiet -dumpbase gfbug120.f -mtune=generic -march=x86-64 -auxbase gfbug120 -version -o gfbug120.s -fintrinsic-modules-path /home/vitti/local/gcc-5.2.0-sanitized/lib/gcc/x86_64-unknown-linux-gnu/5.2.0/finclude GNU Fortran (GCC) version 5.2.0 (x86_64-unknown-linux-gnu) compiled by GNU C version 5.2.0, GMP version 6.0.0, MPFR version 3.1.2, MPC version 1.0.2 GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072 GNU Fortran2008 (GCC) version 5.2.0 (x86_64-unknown-linux-gnu) compiled by GNU C version 5.2.0, GMP version 6.0.0, MPFR version 3.1.2, MPC version 1.0.2 GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072 ../../gcc-5.2.0/gcc/fortran/trans-expr.c:5701:19: runtime error: member call on null pointer of type 'struct vec' ../../gcc-5.2.0/gcc/fortran/trans-expr.c:5704:19: runtime error: member call on null pointer of type 'struct vec' ../../gcc-5.2.0/gcc/fortran/trans-expr.c:5707:19: runtime error: member call on null pointer of type 'struct vec' COMPILER_PATH=/home/vitti/local/gcc-5.2.0-sanitized/libexec/gcc/x86_64-unknown-linux-gnu/5.2.0/:/home/vitti/local/gcc-5.2.0-sanitized/libexec/gcc/x86_64-unknown-linux-gnu/5.2.0/:/home/vitti/local/gcc-5.2.0-sanitized/libexec/gcc/x86_64-unknown-linux-gnu/:/home/vitti/local/gcc-5.2.0-sanitized/lib/gcc/x86_64-unknown-linux-gnu/5.2.0/:/home/vitti/local/gcc-5.2.0-sanitized/lib/gcc/x86_64-unknown-linux-gnu/ LIBRARY_PATH=/home/vitti/local/gcc-5.2.0-sanitized/lib/gcc/x86_64-unknown-linux-gnu/5.2.0/:/home/vitti/local/gcc-5.2.0-sanitized/lib/gcc/x86_64-unknown-linux-gnu/5.2.0/../../../../x86_64-unknown-linux-gnu/lib/../lib64/:/home/vitti/local/gcc-5.2.0-sanitized/lib/gcc/x86_64-unknown-linux-gnu/5.2.0/../../../../lib64/:/lib/../lib64/:/usr/lib/../lib64/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/ipp/../compiler/lib/intel64/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/ipp/lib/intel64/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/compiler/lib/intel64/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/tbb/lib/intel64/gcc4.4/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/mkl/lib/intel64/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/tbb/lib/intel64/gcc4.1/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/daal/lib/intel64_lin/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/daal/../tbb/lib/intel6 4_lin/gcc4.4/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/daal/../compiler/lib/intel64_lin/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/tbb/lib/intel64/gcc4.1/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/ipp/../compiler/lib/intel64/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/ipp/lib/intel64/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/compiler/lib/intel64/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/tbb/lib/intel64/gcc4.4/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/mkl/lib/intel64/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/tbb/lib/intel64/gcc4.1/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/daal/lib/intel64_lin/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/daal/../tbb/lib/intel64_lin/gcc4.4/:/home/vitti/intel/compilers_and_libraries_2016.0.069/linux/daal/../compiler/lib/intel64_lin/:/home/vitti/intel/compilers_and_libraries_2016.0.06 9/linux/tbb/lib/intel64/gcc4.1/:/home/vitti/local/gcc-5.2.0-sanitized/lib/gcc/x86_64-unknown-linux-gnu/5.2.0/../../../../x86_64-unknown-linux-gnu/lib/:/home/vitti/local/gcc-5.2.0-sanitized/lib/gcc/x86_64-unknown-linux-gnu/5.2.0/../../../:/lib/:/usr/lib/ COLLECT_GCC_OPTIONS='-v' '-S' '-mtune=generic' '-march=x86-64'