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// RUN: %clang_analyze_cc1 %s \
// RUN: -analyzer-checker=core \
// RUN: -analyzer-checker=debug.ExprInspection \
// RUN: -analyzer-config eagerly-assume=false \
// RUN: -verify
// Here we test that if it turns out that the parent state is infeasible then
// both children States (more precisely the ExplodedNodes) are marked as a
// Sink.
// We rely on existing defects of the underlying constraint solver. However,
// in the future we might strengthen the solver to discover the infeasibility
// right when we create the parent state. At that point some of these tests
// will fail, and either we shall find another solver weakness to have the test
// case functioning, or we shall simply remove that.
void clang_analyzer_warnIfReached();
void clang_analyzer_eval(int);
void test1(int x) {
if (x * x != 4)
return;
if (x < 0 || x > 1)
return;
// { x^2 == 4 and x:[0,1] }
// This state is already infeasible.
// Perfectly constraining 'x' will trigger constant folding,
// when we realize we were already infeasible.
// The same happens for the 'else' branch.
if (x == 0) {
clang_analyzer_warnIfReached(); // no-warning
} else {
clang_analyzer_warnIfReached(); // no-warning
}
clang_analyzer_warnIfReached(); // no-warning
(void)x;
}
int a, b, c, d, e;
void test2() {
if (a == 0)
return;
if (e != c)
return;
d = e - c;
b = d;
a -= d;
if (a != 0)
return;
clang_analyzer_warnIfReached(); // expected-warning{{REACHABLE}}
/* The BASELINE passes these checks ('wrning' is used to avoid lit to match)
// The parent state is already infeasible, look at this contradiction:
clang_analyzer_eval(b > 0); // expected-wrning{{FALSE}}
clang_analyzer_eval(b <= 0); // expected-wrning{{FALSE}}
// Crashes with expensive checks.
if (b > 0) {
clang_analyzer_warnIfReached(); // no-warning, OK
return;
}
// Should not be reachable.
clang_analyzer_warnIfReached(); // expected-wrning{{REACHABLE}}
*/
// The parent state is already infeasible, but we realize that only if b is
// constrained.
clang_analyzer_eval(b > 0); // expected-warning{{UNKNOWN}}
clang_analyzer_eval(b <= 0); // expected-warning{{UNKNOWN}}
if (b > 0) {
clang_analyzer_warnIfReached(); // no-warning
return;
}
clang_analyzer_warnIfReached(); // no-warning
}
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