On May 13, 2016 7:22:37 PM GMT+02:00, Jakub Jelinek <ja...@redhat.com> wrote:
>Hi!
>
>Since a recent change, TYPE_ALIAS_SET of types can change during
>folding.
>This patch arranges for it not to be checksummed.
>
>Bootstrapped/regtested on x86_64-linux and i686-linux (normal
>bootstrap)
>and built (nonbootstrap) + regtested the
>--enable-checking=yes,extra,fold,rtl version (previously it wouldn't
>build
>even libgcc).
>
>Ok for trunk?
OK.
Richard.
>2016-05-13 Jakub Jelinek <ja...@redhat.com>
>
> PR bootstrap/71071
> * fold-const.c (fold_checksum_tree): Allow modification
> of TYPE_ALIAS_SET during folding.
>
> * gcc.dg/pr71071.c: New test.
>
>--- gcc/fold-const.c.jj 2016-05-13 13:58:12.381020172 +0200
>+++ gcc/fold-const.c 2016-05-13 14:22:51.724912335 +0200
>@@ -12130,7 +12130,8 @@ fold_checksum_tree (const_tree expr, str
> || TYPE_REFERENCE_TO (expr)
> || TYPE_CACHED_VALUES_P (expr)
> || TYPE_CONTAINS_PLACEHOLDER_INTERNAL (expr)
>- || TYPE_NEXT_VARIANT (expr)))
>+ || TYPE_NEXT_VARIANT (expr)
>+ || TYPE_ALIAS_SET_KNOWN_P (expr)))
> {
> /* Allow these fields to be modified. */
> tree tmp;
>@@ -12140,6 +12141,7 @@ fold_checksum_tree (const_tree expr, str
> TYPE_POINTER_TO (tmp) = NULL;
> TYPE_REFERENCE_TO (tmp) = NULL;
> TYPE_NEXT_VARIANT (tmp) = NULL;
>+ TYPE_ALIAS_SET (tmp) = -1;
> if (TYPE_CACHED_VALUES_P (tmp))
> {
> TYPE_CACHED_VALUES_P (tmp) = 0;
>--- gcc/testsuite/gcc.dg/pr71071.c.jj 2016-05-13 14:23:39.528278177
>+0200
>+++ gcc/testsuite/gcc.dg/pr71071.c 2016-05-13 14:22:08.000000000 +0200
>@@ -0,0 +1,12 @@
>+/* PR bootstrap/71071 */
>+/* { dg-do compile } *
>+/* { dg-options "-O2" } */
>+
>+struct S { unsigned b : 1; } a;
>+
>+void
>+foo ()
>+{
>+ if (a.b)
>+ ;
>+}
>
> Jakub
