On 06/30/2015 03:06 AM, Eric Botcazou wrote:
>> I notice the way gcc_assert() is defined in system.h now, the test won't
>> disappear even when runtime checks are disabled, though you might still
>> adjust it to avoid any programmer confusion.
>
> It will disappear at run time, see the definition:
>
> /* Include EXPR, so that unused variable warnings do not occur.  */
> #define gcc_assert(EXPR) ((void)(0 && (EXPR)))
>
> so you really need to use a separate variable.

Oh, yuck -- it never even occurred to me that gcc_assert could be 
disabled.  I'll bet there are other bugs in GCC due to this very same 
problem of depending on its argument being executed for side-effect. 
(E.g. take a look at add_stmt_to_eh_lp_fn in tree-eh.c.)  Seems like 
lousy design to me especially since proper usage doesn't seem to be 
documented anywhere.

Anyway, I think the attached patch is what's required to fix the 
instance that's my fault.  OK?  Bernd, if this needs testing, can you help?

-Sandra