Re: [PATCH] gimple-fold.h: Add missing gimple-iterator.h

[Richard Biener <richard.guenther@gmail.com>]

On Thu, Jan 12, 2023 at 2:46 AM Palmer Dabbelt <palmer@rivosinc.com> wrote:
>
> As of 6f5b06032eb ("Finish gimple_build API enhancement") gimple-fold.h
> uses some of the declarations from gimple-iterator.h, which causes
> issues when building Linux's stackprotector plugin.
>
> gcc/ChangeLog:
>
>         * gimple-fold.h: Add gimple-iterator.h include.
>
> ---
>
> I'm not sure if this should instead be fixed in Linux by reordering the
> includes along the lines of
>
> diff --git a/scripts/gcc-plugins/gcc-common.h b/scripts/gcc-plugins/gcc-common.h
> index 9a1895747b15..2c3a3079128a 100644
> --- a/scripts/gcc-plugins/gcc-common.h
> +++ b/scripts/gcc-plugins/gcc-common.h
> @@ -72,6 +72,7 @@
>  #include "stor-layout.h"
>  #include "internal-fn.h"
>  #include "gimple-expr.h"
> +#include "gimple-iterator.h"
>  #include "gimple-fold.h"
>  #include "context.h"
>  #include "tree-ssa-alias.h"
> @@ -88,7 +89,6 @@
>  #include "gimple.h"
>  #include "tree-phinodes.h"
>  #include "tree-cfg.h"
> -#include "gimple-iterator.h"
>  #include "gimple-ssa.h"
>  #include "ssa-iterators.h"

The above change is OK.

> but I figured it was slightly easier for users to keep these compatible.
> It looks like many GCC-internal uses of gimple-fold.h already have the
> gimple-iterator.h include right before, though, so not sure if that's
> how things are meant to be.
> ---
>  gcc/gimple-fold.h | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/gcc/gimple-fold.h b/gcc/gimple-fold.h
> index 2fd58db9a2e..66bee2b75df 100644
> --- a/gcc/gimple-fold.h
> +++ b/gcc/gimple-fold.h
> @@ -22,6 +22,8 @@ along with GCC; see the file COPYING3.  If not see
>  #ifndef GCC_GIMPLE_FOLD_H
>  #define GCC_GIMPLE_FOLD_H
>
> +#include "gimple-iterator.h"
> +

But this is not - we try to avoid #include directives in headers, we want the
include dependences to be "flat"

>  extern tree create_tmp_reg_or_ssa_name (tree, gimple *stmt = NULL);
>  extern tree canonicalize_constructor_val (tree, tree);
>  extern tree get_symbol_constant_value (tree);
> --
> 2.39.0
>