[gentoo-user] llvm fails to emerge

[n952162]

I'm trying to emerge x11-base/xorg-x11 but unfortunately, it depends on
llvm, and that fails to build:

{standard input}: Assembler messages:
{standard input}:27335: Warning: end of file not at end of a line;
newline inserted
{standard input}: Error: open CFI at the end of file; missing
.cfi_endproc directive
{standard input}:28038: Error: invalid operands (*UND* and
.gcc_except_table._ZN4llvm19SelectionDAGBuilder18emitInlineAsmErrorENS_17ImmutableCallSiteERKNS_5TwineE
sections) for `-'
x86_64-pc-linux-gnu-g++: fatal error: Killed signal terminated program
cc1plus
compilation terminated.
ninja: build stopped: subcommand failed.
  * ERROR: sys-devel/llvm-10.0.1::gentoo failed (compile phase):
  *   ninja -v -j1 -l0 failed

I think I've run into similar kinds of errors before, which may have be
due to demanding too much from my vbox, so I tried setting -j1, but that
didn't help.

Any ideas?

TIA