tmp/tmpthra8ibw/{from.md → to.md}
RENAMED
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| 1 |
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### Indeterminate storage <a id="dcl.attr.indet">[[dcl.attr.indet]]</a>
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The *attribute-token* `indeterminate` may be applied to the definition
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of a block variable with automatic storage duration or to a
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*parameter-declaration* of a function declaration. No
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*attribute-argument-clause* shall be present. The attribute specifies
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that the storage of an object with automatic storage duration is
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initially indeterminate rather than erroneous [[basic.indet]].
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If a function parameter is declared with the `indeterminate` attribute,
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it shall be so declared in the first declaration of its function. If a
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function parameter is declared with the `indeterminate` attribute in the
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first declaration of its function in one translation unit and the same
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function is declared without the `indeterminate` attribute on the same
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parameter in its first declaration in another translation unit, the
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program is ill-formed, no diagnostic required.
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[*Note 1*:
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Reading from an uninitialized variable that is marked
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`[[indeterminate]]` can cause undefined behavior.
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``` cpp
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void f(int);
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void g() {
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int x [[indeterminate]], y;
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f(y); // erroneous behavior[basic.indet]
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f(x); // undefined behavior
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}
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struct T {
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T() {}
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int x;
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};
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int h(T t [[indeterminate]]) {
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f(t.x); // undefined behavior when called below
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return 0;
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}
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int _ = h(T());
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```
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— *end note*]
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