[Bug preprocessor/53404] warning column reported on comment in warning during bootstrap

["egallager at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53404

--- Comment #4 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to Eric Gallager from comment #3)
> (In reply to Manuel López-Ibáñez from comment #2)
> > I don't see this any longer.
> 
> I think I might've seen this before, but I'll have to double-check the next
> time I bootstrap to make sure

The warnings I get from gengtype-lex.c when bootstrapping are now:

../../gcc/gengtype-lex.l: In function ‘int yylex(const char**)’:
gengtype-lex.c:287:13: warning: this statement may fall through
[-Wimplicit-fallthrough=]
  *yy_cp = '\0'; \
  ~~~~~~~~~~~^~~
../../gcc/gengtype-lex.l:116:1: note: in expansion of macro
‘YY_DO_BEFORE_ACTION’
     *yylval = XDUPVAR (const char, yytext, yyleng, yyleng + 1);
 ^   ~~~~~~~~~~~~~~~
../../gcc/gengtype-lex.l:113:1: note: here
 "~"     |
 ^~~~
gengtype-lex.c:287:13: warning: this statement may fall through
[-Wimplicit-fallthrough=]
  *yy_cp = '\0'; \
  ~~~~~~~~~~~^~~
../../gcc/gengtype-lex.l:133:1: note: in expansion of macro
‘YY_DO_BEFORE_ACTION’

 ^                  
../../gcc/gengtype-lex.l:131:1: note: here
 "ENUM_BITFIELD"{WS}?"("{WS}?{ID}{WS}?")" {
 ^~~~

...which is no longer in a comment, but it still seems like there's some wrong
location information involved. Separate issue or the same thing?