> On 03/20/2015 02:20 AM, Ilya Enkovich wrote: > >Hi, > > > >Identifiers read with input_identifier miss IDENTIFIER_TRANSPARENT_ALIAS > >bit. We always expect it for instrumentation clones, thus restore it > >input_cgraph_1. Bootstrapped and tested on x86_64-unknown-linux-gnu. OK > >for trunk? > > > >Thanks, > >Ilya > >-- > >2015-03-20 Ilya Enkovich <ilya.enkov...@intel.com> > > > > * lto-cgraph.c (input_cgraph_1): Always link instrumented > > assembler name with original one. > This appears to be a code path that only triggers when MPX is > enabled and is roughly analogous to the code in > chkp_build_instrumented_fndecl links things up. > > OK for the trunk.
I think this will lead to wrong code. At this time, we may have multple declarations sharing single assembler name (and thus IDENTIFIER_TRANSPARENT_ALIAS link). Think of case where one unit defines static function and other global function of the same name. We may end up renaming the symbol but keeping bogus transparent alias link that will trigger on other symbol. During WPA the assembler names are never fully unique, but we also probably do not need to set IDENTIFIER_TRANSPARENT_ALIAS. I think IDENTIFIER_TRANSPARENT_ALIAS should be set in rename_statics and separately in ltrans on the place we skip lto_symtab merging. At least it is the place I link it with my patch for supporting transparent aliases in cgraph. I will try to find time to audit chkp code - I missed the addition of transparent aliases in the initial chkp patches. Symbol table code expect 1-1 correspondence between symbol table entries and real symbols. Basically all places we special case aliases or weakrefs needs to be revisited for transparent aliases. Honza
