Re: Patch to remove undefined C code

[Ben Pfaff]

Jonathan George <[EMAIL PROTECTED]> writes:

> This patch has many bogus corrections where new variables were created, but
> the order of evaluation is already unambiguous.
> 
> For example each comma separated clause in an expression is guaranteed to be
> completely evaluated before the next comma separated clause Including
> Assignments.

No, that is not true in general.  When the comma in question is
the comma operator, it is true.  But when the comma separates
arguments to a function, it is not: the order of evaluation of
function arguments is implementation dependent.  See C89 section
6.3.2.2 "Function calls":

        $ The order of evaluation of the function designator, the
        $ arguments, and subexpressions within the arguments is
        $ unspecified, ...
-- 
"Premature optimization is the root of all evil."
--D. E. Knuth, "Structured Programming with go to Statements"
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