https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95381
--- Comment #3 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> --- (In reply to John Paul Adrian Glaubitz from comment #2) > (In reply to Richard Biener from comment #1) > > can we have a backtrace? > > Working on it. I'm at the point now where I can invoke the command which provokes the crash: (sid-m68k-sbuild)root@epyc:/build/gcc-snapshot-t0p5re/gcc-snapshot-20200525/build-jit/gcc# /build/gcc-snapshot-t0p5re/gcc-snapshot-20200525/build-jit/./gcc/xgcc -B/build/gcc-snapshot-t0p5re/gcc-snapshot-20200525/build-jit/./gcc/ -xc++ -nostdinc /dev/null -S -o /dev/null -fself-test=../../src/gcc/testsuite/selftests cc1plus: internal compiler error: in operator[], at vec.h:867 mmap: Bad file descriptor close: Bad file descriptor Please submit a full bug report, with preprocessed source if appropriate. See <file:///usr/share/doc/gcc-snapshot/README.Bugs> for instructions. (sid-m68k-sbuild)root@epyc:/build/gcc-snapshot-t0p5re/gcc-snapshot-20200525/build-jit/gcc# What kind of backtrace are you looking for? Through GDB?