On Fri, May 14, 2010 at 9:33 PM, Eric Botcazou <ebotca...@adacore.com> wrote: >> Ugh. This presents a chicken-and-egg problem to symbol resolution >> and type-merging. >> >> To be clear, the issue is sth like >> >> unit1 >> ----- >> int size; >> int a[size]; >> >> unit2 >> ------ >> extern int size; >> extern a[size]; >> >> ? And you get the a's merged but a diagnostic about mismatched types? > > Yes, exactly. > >> One way to fix this would be to simply detect the situation and never >> issue a diagnostic. Another way would be to delay the diagnostics >> until after all types and symbols are merged. The natural place >> for this would be lto_symtab_merge_cgraph_nodes () which already >> is after type merging and still has all candidates available. > > Is suppressing the diagnostic sufficient? Will the two types be merged after > the symbols are unified, or does that not matter at all?
The types will not be unified. We are currently inserting VIEW_CONVERT_EXPRs to make the IL type verification happy, but in the end it will cause broken type-based alias info and thus may trigger miscompiles. I am in the process of fixing both pieces (avoid the V_C_E by using MEM_REF and avoid the miscompile by separating TBAA types from the IL types). Richard. > -- > Eric Botcazou >
