[Bug modula2/114529] profiledbootstrap fails to build and m2 causes odr violations during build

[gaius at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114529

--- Comment #3 from Gaius Mulley <gaius at gcc dot gnu.org> ---
As an aid memoir the configure flags are:

../configure --prefix=$HOME/opt --enable-bootstrap
--with-build-config="bootstrap-O3 bootstrap-lto"
--enable-languages=c,c++,m2,lto

which provoke the odr violation.

m2/gm2-compiler-boot/M2Error.c:421:8: warning: type ‘struct
DynamicStrings_Contents_r’ violates the C++ One Definition Rule [-Wodr]
  421 | struct DynamicStrings_Contents_r {
      |        ^
m2/gm2-compiler-boot/M2GCCDeclare.c:708:8: note: a different type is defined in
another translation unit
  708 | struct DynamicStrings_Contents_r {
      |        ^
m2/gm2-compiler-boot/M2Error.c:422:55: note: the first difference of
corresponding definitions is field ‘buf’
  422 |                                    DynamicStrings__T5 buf;