On Wed, Feb 28, 2018 at 09:11:24AM -0300, Alexandre Oliva wrote:
> Evaluation of constant expressions, such as those passed to
> static_assert, ICEd when encountering IMPLICIT_CONV_EXPRs.
>
> Handle them like CONVERT_EXPR and NOP_EXPR.
>
> Regstrapped on x86_64- and i686-linux-gnu. Ok to install?
>
> for gcc/cp/ChangeLog
>
> PR c++/84596
> * constexpr.c (cxx_eval_constant_expression): Handle
> IMPLICIT_CONV_EXPR.
>
> for gcc/testsuite/ChangeLog
>
> PR c++/84596
> * g++.dg/cpp0x/pr84596.C: New.
> ---
> gcc/cp/constexpr.c | 1 +
> gcc/testsuite/g++.dg/cpp0x/pr84596.C | 7 +++++++
> 2 files changed, 8 insertions(+)
> create mode 100644 gcc/testsuite/g++.dg/cpp0x/pr84596.C
>
> diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
> index 4bbdbf434877..d38e2d83ae8c 100644
> --- a/gcc/cp/constexpr.c
> +++ b/gcc/cp/constexpr.c
> @@ -4549,6 +4549,7 @@ cxx_eval_constant_expression (const constexpr_ctx *ctx,
> tree t,
> non_constant_p, overflow_p);
> break;
>
> + case IMPLICIT_CONV_EXPR:
> case CONVERT_EXPR:
> case VIEW_CONVERT_EXPR:
> case NOP_EXPR:
I don't think it's correct to handle template codes here; they shouldn't
have gotten to cxx_eval_constant_expression in the first place. Usually
they're substituted in instantiate_non_dependent_expr_internal e.g. via
calling fold_non_dependent_expr. So I guess we need to find out how
IMPLICIT_CONV_EXPR has gotten there.
Marek
