Re: [PATCH] Fix ICE caused by a missing check for DECL_LANG_SPECIFIC

[Jason Merrill <jason at redhat dot com>]

On Thu, Mar 1, 2018 at 7:02 AM, Matthew Fortune <mfortune@gmail.com> wrote:
> Hi,
>
> It seems we have had a bug for some time that causes an ICE and prevents the
> MIPS16 library builds from completing but is likely unrelated to MIPS16.
> The problem is when we call target_reinit and library functions get created
> as shown in the call stack at the end of this message. The first builtin
> that triggers the problem happens to be one of the MIPS16 helpers but I
> don't think there is anything unique about it. The issue appeared after some
> refactoring work in r253600 where code testing DECL_CLASS_SCOPE_P and
> DECL_FRIEND_P was previously guarded by a check for DECL_LANG_SPECIFIC but
> not after.
>
> https://gcc.gnu.org/ml/gcc-patches/2017-10/msg00604.html
>
> I don’t know if this is the correct solution or whether we need to change the
> way builtins are initialised in the MIPS backend but I suspect this fix
> is the right way to go.
>
> Cc: Jason as author of the original change.
>
> Thanks,
> Matthew
>
> gcc/cp/
>         * pt.c (type_dependent_expression_p): Add missing check for
>         DECL_LANG_SPECIFIC.
> ---
>  gcc/cp/pt.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
> index 7345119..c88304f 100644
> --- a/gcc/cp/pt.c
> +++ b/gcc/cp/pt.c
> @@ -24635,6 +24635,7 @@ type_dependent_expression_p (tree expression)
>       type-dependent.  Checking this is important for functions with auto return
>       type, which looks like a dependent type.  */
>    if (TREE_CODE (expression) == FUNCTION_DECL
> +      && DECL_LANG_SPECIFIC (expression)
>        && !(DECL_CLASS_SCOPE_P (expression)
>            && dependent_type_p (DECL_CONTEXT (expression)))
>        && !(DECL_FRIEND_P (expression)

I think we want to go into this block when DECL_LANG_SPECIFIC is NULL.
Does this also fix the issue for you?

Attachment: friend.diff
Description: Text document