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Re: Volatile MEMs in statement expressions and functions inlined as trees
Linus Torvalds <torvalds@transmeta.com> writes:
| In article <fln10n370l.fsf@riz.cmla.ens-cachan.fr> you write:
| >
| >Absolutely not. Please re-read what Jason said -- the result of the
| >assignment is an *lvalue*. Thus
| >
| > p = 0;
| >
| >is equivalent to
| >
| > (p = 0, &p);
|
| You and Jason must be on drugs.
Not more than you must be.
[...]
| I stand by my argument.
Not just because you stand by your argument, it will make your claims right.
| Whether you _use_ the value of an assignment or
| not MUST NOT CHANGE THE SEMANTICS OF THE ASSIGNMENT.
In C++, it does. That comes from the lvalue-to-rvalue transformation.
| The fact that a
| C++ compiler thinks that an assignment is also an lvalue does not change
| things one _iota_. Jasons arguments that it has any relevance are
| illogical, and make no sense, simply because the equivalence that he
| (and you) claim exists obviously does NOT exist.
That equivalence is based on the (C++) standards text. You're free to
disagree how things are in C++, but not just because you disagree with
C++ makes GCC behaviour not conformant.
[...]
You have it wrong. Go and check out.
[...]
| And _everybody_ agrees with the fact that "p = 0" should _not_ read the
| value of "p". Thus "q = p = 0" should _also_ not read the value of "p",
That is true in C, not in C++. That was already explained. You're
free to disagree, but not just you disagree means our reading is
incorrect.
-- Gaby