On 10/12/2015 11:57 PM, Jeff Law wrote:
>>> -#ifdef ENABLE_CHECKING
>>> +#if CHECKING_P
>>
>> I fail to see the point of this change.
> I'm guessing (and Mikhail, please correct me if I'm wrong), but I think he's
> trying to get away from ENABLE_CHECKING and instead use a macro which is
> always defined to a value.
Yes, exactly. Such macro is better because it can be used both for conditional
compilation (if needed) and normal if-s (unlike ENABLE_CHECKING).

On 10/14/2015 12:33 AM, Jeff Law wrote:
>>   gcc/common.opt  | 5 +++++
>>   gcc/system.h    | 3 +++
>>   libcpp/system.h | 8 ++++++++
>>   3 files changed, 16 insertions(+)
> I committed this prerequisite patch to the trunk.
> 
> jeff
> 

There is a typo here:

> #ifdef ENABLE_CHECKING
> #define gcc_checking_assert(EXPR) gcc_assert (EXPR)
>+#define CHECKING_P 1
> #else
>+/* N.B.: in release build EXPR is not evaluated.  */
> #define gcc_checking_assert(EXPR) ((void)(0 && (EXPR)))
>+#define CHECKING_P 1
> #endif

In my original patch the second definition actually was
'+#define CHECKING_P 0'

Also, gcc_checking_assert in libcpp requires gcc_assert to be defined. That was
missing in my original patch (and was added in patch 2/9), but I think it would
be better to fix it here, as Bernd noticed (in the last paragraph of [1]).

Besides, I like Richard's proposal [2] about moving CHECKING_P macros into
configure.ac.

[1] https://gcc.gnu.org/ml/gcc-patches/2015-10/msg00550.html
[2] https://gcc.gnu.org/ml/gcc-patches/2015-10/msg00555.html

It required minor tweaking in order to silence autotools' warnings. I attached
the modified patch.

OK for trunk (after bootstrap/regtest)?

P.S. I am planning to post at least some of the other updated parts today, and I
also hope to get in time with the whole series (before stage1 ends).

-- 
Regards,
    Mikhail Maltsev

gcc/ChangeLog:

2015-10-18  Mikhail Maltsev  <maltsevm@gmail.com>

        * config.in: Regenerate.
        * configure: Regenerate.
        * configure.ac (CHECKING_P): Define.
        * system.h: Use CHECKING_P.

libcpp/ChangeLog:

2015-10-18  Mikhail Maltsev  <maltsevm@gmail.com>

        * config.in: Regenerate.
        * configure: Regenerate.
        * configure.ac (CHECKING_P): Define.
        * system.h (fancy_abort): Declare.
        (abort): Define.
        (gcc_assert): Define. Use CHECKING_P.