https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87757
Aldy Hernandez <aldyh at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2018-10-30
Ever confirmed|0 |1
--- Comment #5 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
(In reply to David Malcolm from comment #4)
> Aldy: do you remember why the arguments need to have the same location as
> the call itself?
>
> The first case works because during gimplify_arg it's wrapped in a NOP_EXPR
> which is casting from char[] to char *, and it's this NOP_EXPR which gets
> its location modified.
>
> The second case doesn't have the NOP_EXPR.
This looks like an oversight on my part.
In the original patch you mention, there was a now defunct bit that seems
suspicious and my shed light on the problem:
+ /* FIXME diagnostics: This should be the location of the argument,
+ not the FNDECL. E.g., for an old-style declaration
+
+ int f10(v) { blah; }
+
+ We should use the location of the V, not the F10.
+ Unfortunately, the V is an IDENTIFIER_NODE which has no
+ location. In the future we need locations for c_arg_info
+ entries.
+
+ See gcc.dg/Wshadow-3.c for an example of this problem. */
So maybe I was assuming that the problematic line was also dealing with an
IDENTIFIER_NODE which had no place to put a location?
Either way, it looks like some sort of oversight.
Confirmed, BTW.
