Description
An issue has been submitted in upstream crosstool-NG (crosstool-ng/crosstool-ng#698) and while looking at it, I tried to build a configuration using an overlay, xtensa_lx106.tar. It failed.
The reason for the failure is that the newlib portion of the overlay is extracted into a wrong directory. The overlay tarball is extracted using the tar --strip-components=1 -xv -f /home/avn/work/ctng/xtensa/crosstool-ng/overlays/xtensa_lx106.tar newlib command. The contents of the archive is as follows:
binutils/
binutils/ld/
binutils/bfd/
binutils/bfd/xtensa-modules.c
binutils/include/
binutils/include/xtensa-config.h
gcc/
gcc/include/
gcc/include/xtensa-config.h
gdb/
gdb/gdb/
gdb/gdb/gdbserver/
gdb/gdb/gdbserver/xtensa-xtregs.c
gdb/gdb/regformats/
gdb/gdb/regformats/reg-xtensa.dat
gdb/gdb/xtensa-config.c
gdb/bfd/
gdb/bfd/xtensa-modules.c
gdb/include/
gdb/include/xtensa-config.h
newlib/
newlib/libc/
newlib/libc/sys/
newlib/libc/sys/xtensa/
newlib/libc/sys/xtensa/include/
newlib/libc/sys/xtensa/include/xtensa/
newlib/libc/sys/xtensa/include/xtensa/config/
newlib/libc/sys/xtensa/include/xtensa/config/core-isa.h
The newlib build fails because the newlib-2.0.0/newlib/libc/sys/xtensa/include/xtensa/config/core-isa.h file is missing. Accounting for the first stripped path component, this file should have been packaged as newlib/newlib/libc/sys/xtensa/include/xtensa/config/core-isa.h (i.e. one level deeper in the directory tree).
The build does not fail in this fork because one of the local patches (local-patches/newlib/2.0.0/0002-xtensa-cleanups.patch) creates this missing file.
The other two overlays in the overlays/ directory have the newlib packaged correctly. E.g. in esp32 overlay:
newlib/newlib/libc/sys/xtensa/include/xtensa/config/core-isa.h
With that fixed, newlib still fails though ("Newlib does not support CPU xtensa") - it looks like your local patches need to be ported upstream, to crosstool-NG and/or newlib.