https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55252
--- Comment #18 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #17)
> It would be less of a pain if -Wsystem-headers caused both locations to be
> printed, but it doesn't, so sometimes the only option is to dump the
> preprocessed source without line markers and then compile that to get two
> locations, then map the location in the preprocessed source back to a line
> in the original source.
You could try with this:
Index: tree-diagnostic.c
===================================================================
--- tree-diagnostic.c (revision 220306)
+++ tree-diagnostic.c (working copy)
@@ -197,12 +197,14 @@ maybe_unwind_expanded_macro_loc (diagnos
within a system header. */
const struct line_map *m = NULL;
source_location l =
linemap_resolve_location (line_table, resolved_def_loc,
LRK_SPELLING_LOCATION, &m);
- if (l < RESERVED_LOCATION_COUNT || LINEMAP_SYSP (m))
- continue;
+ if (l < RESERVED_LOCATION_COUNT)
+ continue;
+ if (LINEMAP_SYSP (m) && !context->dc_warn_system_headers)
+ continue;
/* We need to print the context of the macro definition only
when the locus of the first displayed diagnostic (displayed
before this trace) was inside the definition of the
macro. */
.. but I still not see why we need to skip system-headers at all. The comment
in the original patch (r186970)
I am then using that facility in the diagnostics printing module and
in the macro unwinder to avoid printing diagnostics lines that refer
to the locations for built-ins or more generally for reserved
locations. Note that when I start the dance of skipping a built-in
location I also skip locations that are in system headers, because it
turned out that a lot of those built-ins are actually used in system
headers (e.g, "#define INT_MAX __INT_MAX__" where __INT_MAX__ is a
built-in).
suggests that we do not want to give a note for the #define, but it seems a
small price to pay for getting the other cases right.
