[Simh] clang (was Re: XCode and LTO)

[Sergey Oboguev]

Splitting into separate files won't override optimization in LTO case since 
(tautologically) it is link-time.



----- Original Message ----
From: Nelson H. F. Beebe <beebe at math.utah.edu>
To: Sergey Oboguev <oboguev at yahoo.com>; "simh at trailing-edge.com" 
<simh at trailing-edge.com>
Cc: beebe at math.utah.edu
Sent: Fri, April 27, 2012 10:48:42 AM
Subject: Re: [Simh] clang (was Re: XCode and LTO)

>> Declaring "loopval" as volatile (and perhaps global, rather than on-stack, to 

>> reduce chances of compiler disregarding volatile declaration) might do the 
>> trick.

Yes, that should work if the compiler obeys volatile declarations.  Otherwise,
a store subterfuge will work too:

(a)    volatile int foo;

(b)    int foo;
    ...
    store(&foo);

    In another file:
    void store(int *x) { }

Both cases should force the compiler to load foo from memory, and
not optimize it away.

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