[Bug lto/79061] [7 Regression][LTO][ASAN] LTO plus ASAN fails with "AddressSanitizer: initialization-order-fiasco"

[m.ostapenko at samsung dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79061

--- Comment #14 from Maxim Ostapenko <m.ostapenko at samsung dot com> ---
(In reply to Richard Biener from comment #13)
> (In reply to Maxim Ostapenko from comment #12)
> > Created attachment 40525 [details]
> > Untested fix 2.
> > 
> > The patch I'm testing now.
> 
> DECL_SOURCE_LOCATION is streamed for all decls already:
> 
>   if (CODE_CONTAINS_STRUCT (code, TS_DECL_MINIMAL))
>     stream_output_location (ob, &bp, DECL_SOURCE_LOCATION (expr));

Aha, right, thank you. But it seems that stream_output_location fails to find
it in the location cache that's probably caused by this line in lto.c:

          /* We have the special case of size-1 SCCs that are pre-merged
             by means of identifier and string sharing for example.
             ???  Maybe we should avoid streaming those as SCCs.  */
          tree first = streamer_tree_cache_get_tree (data_in->reader_cache,
                                                     from);
          if (len == 1 
              && (TREE_CODE (first) == IDENTIFIER_NODE
                  || TREE_CODE (first) == INTEGER_CST
                  || TREE_CODE (first) == TRANSLATION_UNIT_DECL))
            continue;

that prohibits 

          /* Tree merging failed, mark entries in location cache as
             permanent.  */
          data_in->location_cache.accept_location_cache ();

several lines below. Perhaps we can just remove TREE_CODE (first) ==
TRANSLATION_UNIT_DECL from the condition?