forked from OSchip/llvm-project
142 lines
2.5 KiB
C
142 lines
2.5 KiB
C
// RUN: %clang_cc1 -analyze -analyzer-checker=core,deadcode.DeadStores,alpha.deadcode.UnreachableCode -verify -analyzer-opt-analyze-nested-blocks -Wno-unused-value %s
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extern void foo(int a);
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// The first few tests are non-path specific - we should be able to find them
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void test(unsigned a) {
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switch (a) {
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a += 5; // expected-warning{{never executed}}
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case 2:
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a *= 10;
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case 3:
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a %= 2;
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}
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foo(a);
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}
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void test2(unsigned a) {
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help:
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if (a > 0)
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return;
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if (a == 0)
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return;
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foo(a); // expected-warning{{never executed}}
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goto help;
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}
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void test3(unsigned a) {
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while(1);
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if (a > 5) { // expected-warning{{never executed}}
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return;
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}
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}
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// These next tests are path-sensitive
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void test4() {
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int a = 5;
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while (a > 1)
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a -= 2;
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if (a > 1) {
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a = a + 56; // expected-warning{{never executed}}
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}
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foo(a);
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}
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extern void bar(char c);
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void test5(const char *c) {
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foo(c[0]);
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if (!c) {
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bar(1); // expected-warning{{never executed}}
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}
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}
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// These next tests are false positives and should not generate warnings
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void test6(const char *c) {
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if (c) return;
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if (!c) return;
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__builtin_unreachable(); // no-warning
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}
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// Compile-time constant false positives
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#define CONSTANT 0
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enum test_enum { Off, On };
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void test7() {
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if (CONSTANT)
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return; // no-warning
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if (sizeof(int))
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return; // no-warning
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if (Off)
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return; // no-warning
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}
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void test8() {
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static unsigned a = 0;
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if (a)
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a = 123; // no-warning
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a = 5;
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}
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// Check for bugs where multiple statements are reported
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void test9(unsigned a) {
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switch (a) {
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if (a) // expected-warning{{never executed}}
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foo(a + 5); // no-warning
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else // no-warning
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foo(a); // no-warning
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case 1:
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case 2:
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break;
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default:
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break;
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}
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}
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// Tests from flow-sensitive version
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void test10() {
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goto c;
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d:
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goto e; // expected-warning {{never executed}}
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c: ;
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int i;
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return;
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goto b; // expected-warning {{never executed}}
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goto a; // expected-warning {{never executed}}
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b:
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i = 1; // no-warning
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a:
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i = 2; // no-warning
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goto f;
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e:
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goto d;
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f: ;
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}
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// test11: we can actually end up in the default case, even if it is not
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// obvious: there might be something wrong with the given argument.
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enum foobar { FOO, BAR };
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extern void error();
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void test11(enum foobar fb) {
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switch (fb) {
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case FOO:
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break;
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case BAR:
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break;
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default:
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error(); // no-warning
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return;
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error(); // expected-warning {{never executed}}
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}
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}
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