OK.
On Tue, Mar 7, 2017 at 2:00 PM, Jakub Jelinek <ja...@redhat.com> wrote:
> Hi!
>
> Doing copy_node on error_mark_node doesn't work too well, lots of spots
> in the compiler assume there is just a single error_mark_node and compare
> it using pointer comparison, rather than checking for TREE_CODE () ==
> ERROR_MARK. The testcase ICEs in particular during gimplification,
> the CONST_DECL's DECL_INITIAL is not error_mark_node, but some other
> ERROR_MARK and gimplify_expr doesn't like that.
>
> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
> trunk?
>
> 2017-03-07 Jakub Jelinek <ja...@redhat.com>
>
> PR c++/79896
> * decl.c (finish_enum_value_list): If value is error_mark_node,
> don't copy it and change its type.
> * init.c (constant_value_1): Return error_mark_node if DECL_INITIAL
> of CONST_DECL is error_mark_node.
>
> * g++.dg/ext/int128-5.C: New test.
>
> --- gcc/cp/decl.c.jj 2017-03-01 09:31:48.000000000 +0100
> +++ gcc/cp/decl.c 2017-03-07 12:31:23.055294773 +0100
> @@ -14323,9 +14323,12 @@ finish_enum_value_list (tree enumtype)
> input_location = saved_location;
>
> /* Do not clobber shared ints. */
> - value = copy_node (value);
> + if (value != error_mark_node)
> + {
> + value = copy_node (value);
>
> - TREE_TYPE (value) = enumtype;
> + TREE_TYPE (value) = enumtype;
> + }
> DECL_INITIAL (decl) = value;
> }
>
> --- gcc/cp/init.c.jj 2017-03-02 22:30:24.000000000 +0100
> +++ gcc/cp/init.c 2017-03-07 12:41:08.724540062 +0100
> @@ -2162,7 +2162,8 @@ constant_value_1 (tree decl, bool strict
> init = DECL_INITIAL (decl);
> if (init == error_mark_node)
> {
> - if (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
> + if (TREE_CODE (decl) == CONST_DECL
> + || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
> /* Treat the error as a constant to avoid cascading errors on
> excessively recursive template instantiation (c++/9335). */
> return init;
> --- gcc/testsuite/g++.dg/ext/int128-5.C.jj 2017-03-07 12:36:24.617301861
> +0100
> +++ gcc/testsuite/g++.dg/ext/int128-5.C 2017-03-07 12:36:49.388973865 +0100
> @@ -0,0 +1,10 @@
> +// PR c++/79896
> +// { dg-do compile { target { ilp32 && { ! int128 } } } }
> +// { dg-options "" }
> +
> +enum E
> +{
> + e1 = 0xffffffffffffffffULL,
> + e2, // { dg-error "overflow in enumeration values" }
> + e3
> +} e = e3;
>
> Jakub
