On Wed, 11 Feb 2015, Jakub Jelinek wrote:
> Hi!
>
> This patch fixes a thinko in -fsection-anchors alias handling code
> Honza added in r211357. Usually for aliases we don't create
> SYMBOL_REF_HAS_BLOCK_INFO_P, but in the following testcase we do,
> because the rtl is created through notice_global_symbol already
> when the symbol wasn't an alias, only later optimizations made it into
> an alias. The thinko is that DECL_RTL of the alias target would be
> SYMBOL_REF, I think that can't ever happen, usually the DECL_RTL would
> be a MEM with SYMBOL_REF operand.
Yeah, indeed.
> I've bootstrapped/regtested this on
> {x86_64,i686,ppc64,ppc64le,aarch64,armv7hl,s390,s390x}-linux without
> regressions, so I hope the assertion this way is safe, if not, we'd
> need to avoid turning a symbol into an alias somewhere much earlier.
>
> Ok for trunk?
Ok.
Thanks,
Richard.
> 2015-02-11 Jakub Jelinek <ja...@redhat.com>
>
> PR middle-end/65003
> * varasm.c (place_block_symbol): Assert that DECL_RTL of the
> ultimate alias is MEM with SYMBOL_REF satisfying
> SYMBOL_REF_HAS_BLOCK_INFO_P as its operand. Don't pass the MEM
> to place_block_symbol, but instead pass the SYMBOL_REF operand of it.
>
> * g++.dg/opt/pr65003.C: New test.
>
> --- gcc/varasm.c.jj 2015-02-04 15:24:20.000000000 +0100
> +++ gcc/varasm.c 2015-02-10 15:37:55.872609142 +0100
> @@ -7180,6 +7180,10 @@ place_block_symbol (rtx symbol)
> {
> rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
>
> + gcc_assert (MEM_P (target)
> + && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
> + && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
> + target = XEXP (target, 0);
> place_block_symbol (target);
> SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
> return;
> --- gcc/testsuite/g++.dg/opt/pr65003.C.jj 2015-02-10 15:50:44.240734029
> +0100
> +++ gcc/testsuite/g++.dg/opt/pr65003.C 2015-02-10 15:50:39.468814055
> +0100
> @@ -0,0 +1,31 @@
> +// PR middle-end/65003
> +// { dg-do compile }
> +// { dg-options "-O2" }
> +// { dg-additional-options "-fpic" { target fpic } }
> +
> +struct A
> +{
> + void operator= (A &);
> + A ();
> +};
> +struct B
> +{
> + A b;
> +};
> +struct C
> +{
> + virtual bool foo (int &, bool) const;
> +};
> +struct D : virtual C
> +{
> + bool foo (int &, bool) const;
> + B e;
> +};
> +struct F : D
> +{
> + F (int &, const int &, const A &);
> + bool foo (int &, bool) const;
> +};
> +bool D::foo (int &, bool) const {}
> +F::F (int &, const int &, const A &) {}
> +bool F::foo (int &, bool) const {}
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Jennifer Guild,
Dilip Upmanyu, Graham Norton HRB 21284 (AG Nuernberg)
