C++Talk.NET

Kerch Holt · Guest

When jumping past initialization of a local static variable the
value of the static becomes indeterminate. Seems like this
behavior should be illegal just as it is for local variables
with automatic linkage.

Should 6.7 P3 be changed to say "local variable with automatic
or static storage duration"? Or, is this behavior a
"quality of implemenation issue" which may be covered in
6.7 P4? Paragraph 4 seems to make the choice of static/dynamic
initialization indeterminate and would give different results here.

struct X {
X(int i) : x(i) {}
int x;
};
int f(int c) {
if (c)
goto ly; // error here for jumping past next stmt?
static X a = 1;
ly:
return a.x; // either 1 or 0 depending on implementation.
}

I've seen a similar test that uses a switch statement to duplicate
this behavior -- it is not limited to just (evil) gotos.

--
Kerch Holt [email]kerch (AT) cup (DOT) hp.com[/email]
HP Java, Compilers, and Tools Lab (JCTL)
11000 Wolfe Road, MS 4023
Cupertino, CA 95014

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