On Thu, 27 Aug 2015, Richard Biener wrote:
>
> With the passes.c hunk in the patch below we FAIL assembly comparison
> of g++.dg/pch/system-[12].C because with PCH we have computed
> DECL_ASSEMBLER_NAME and thus appended DW_AT_linkage_name early during
> PCH generation while without PCH we compute it lazily and end up
> appending DW_AT_specification earlier. Thus we have swapped dwarf
> attribute order and assembly comparison fails.
>
> Clearly this kind of "IL" changes dependent on whether we are writing
> a PCH file is going to cause differences down the food chain.
> (there is another case in instantiate_decl calling add_pending_template
> dependent on pch_file)
>
> Now a simple solution is to simply not do that (mangle decls). Another
> would be to always mangle decls where we now do so conditional on PCH.
> Another soulution is to declare we don't care about assembly differences
> with/without using PCH and remove assembly comparison from the
> testsuite harness.
>
> Bootstrapped on x86_64-unknown-linux-gnu, testing + gdb testing in
> progress.
>
> Ok for trunk (with note_decl_for_pch completely removed)?
Ping.
The C++ issue prevents me from refactoring late global decl dwarf
and I'd rather not munge that together with this C++ specific issue.
Thanks,
Richard.
> The passes.c hunk is needed because we otherwise miss to properly
> create the early DIEs for those kind of globals (we'll be left
> with a declaration DIE from the type DIE creation and miss the
> definition part).
>
> Thanks,
> Richard.
>
> 2015-08-27 Richard Biener <rguent...@suse.de>
>
> * passes.c (rest_of_decl_compilation): Also call early_global_decl
> on global definitions in type context.
>
> cp/
> * semantics.c (note_decl_for_pch): Do not mangle the decl.
>
> Index: gcc/passes.c
> ===================================================================
> --- gcc/passes.c (revision 227258)
> +++ gcc/passes.c (working copy)
> @@ -318,7 +318,15 @@ rest_of_decl_compilation (tree decl,
> && !decl_function_context (decl)
> && !current_function_decl
> && DECL_SOURCE_LOCATION (decl) != BUILTINS_LOCATION
> - && !decl_type_context (decl)
> + && (!decl_type_context (decl)
> + /* If we created a varpool node for the decl make sure to
> + call early_global_decl. Otherwise we miss changes
> + introduced by member definitions like
> + struct A { static int staticdatamember; };
> + int A::staticdatamember;
> + and thus have incomplete early debug. */
> + || (TREE_CODE (decl) == VAR_DECL
> + && TREE_STATIC (decl) && !DECL_EXTERNAL (decl)))
> /* Avoid confusing the debug information machinery when there are
> errors. */
> && !seen_error ())
> Index: gcc/cp/semantics.c
> ===================================================================
> --- gcc/cp/semantics.c (revision 227258)
> +++ gcc/cp/semantics.c (working copy)
> @@ -2962,15 +2962,21 @@ finish_member_declaration (tree decl)
> translation units which include the PCH file. */
>
> void
> -note_decl_for_pch (tree decl)
> +note_decl_for_pch (tree)
> {
> gcc_assert (pch_file);
>
> + /* ??? This changes debug info with/without PCH as DW_AT_linkage_name
> + attributes are added at different times (early when with PCH
> + or late, via pending assembler names, when without PCH).
> + See g++.dg/pch/system-[12].C. */
> +#if 0
> /* There's a good chance that we'll have to mangle names at some
> point, even if only for emission in debugging information. */
> if (VAR_OR_FUNCTION_DECL_P (decl)
> && !processing_template_decl)
> mangle_decl (decl);
> +#endif
> }
>
> /* Finish processing a complete template declaration. The PARMS are
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
