Add -Wloop-analysis. This warning will fire on for loops which the variables
in the loop conditional do not change.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@155835 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/SemaCXX/warn-loop-analysis.cpp b/test/SemaCXX/warn-loop-analysis.cpp
new file mode 100644
index 0000000..802ce52
--- /dev/null
+++ b/test/SemaCXX/warn-loop-analysis.cpp
@@ -0,0 +1,146 @@
+// RUN: %clang_cc1 -fsyntax-only -Wloop-analysis -verify %s
+
+struct S {
+ bool stop() { return false; }
+ bool keep_running;
+};
+
+void by_ref(int &value) { }
+void by_value(int value) { }
+void by_pointer(int *value) {}
+
+void test1() {
+ S s;
+ for (; !s.stop();) {}
+ for (; s.keep_running;) {}
+ for (int i; i < 1; ++i) {}
+ for (int i; i < 1; ) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (int i; i < 1; ) { ++i; }
+ for (int i; i < 1; ) { return; }
+ for (int i; i < 1; ) { break; }
+ for (int i; i < 1; ) { goto exit_loop; }
+exit_loop:
+ for (int i; i < 1; ) { by_ref(i); }
+ for (int i; i < 1; ) { by_value(i); } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (int i; i < 1; ) { by_pointer(&i); }
+
+ for (int i; i < 1; ++i)
+ for (int j; j < 1; ++j)
+ { }
+ for (int i; i < 1; ++i)
+ for (int j; j < 1; ++i) // expected-warning {{variable 'j' used in loop condition not modified in loop body}}
+ { }
+ for (int i; i < 1; ++i)
+ for (int j; i < 1; ++j) // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ { }
+
+ for (int *i, *j; i < j; ++i) {}
+ for (int *i, *j; i < j;) {} // expected-warning {{variables 'i' and 'j' used in loop condition not modified in loop body}}
+
+ // Dereferencing pointers is ignored for now.
+ for (int *i; *i; ) {}
+}
+
+void test2() {
+ int i, j, k;
+ int *ptr;
+
+ // Testing CastExpr
+ for (; i; ) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; i; ) { i = 5; }
+
+ // Testing BinaryOperator
+ for (; i < j; ) {} // expected-warning {{variables 'i' and 'j' used in loop condition not modified in loop body}}
+ for (; i < j; ) { i = 5; }
+ for (; i < j; ) { j = 5; }
+
+ // Testing IntegerLiteral
+ for (; i < 5; ) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; i < 5; ) { i = 5; }
+
+ // Testing FloatingLiteral
+ for (; i < 5.0; ) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; i < 5.0; ) { i = 5; }
+
+ // Testing CharacterLiteral
+ for (; i == 'a'; ) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; i == 'a'; ) { i = 5; }
+
+ // Testing CXXBoolLiteralExpr
+ for (; i == true; ) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; i == true; ) { i = 5; }
+
+ // Testing GNUNullExpr
+ for (; ptr == __null; ) {} // expected-warning {{variable 'ptr' used in loop condition not modified in loop body}}
+ for (; ptr == __null; ) { ptr = &i; }
+
+ // Testing UnaryOperator
+ for (; -i > 5; ) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; -i > 5; ) { ++i; }
+
+ // Testing ImaginaryLiteral
+ for (; i != 3i; ) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; i != 3i; ) { ++i; }
+
+ // Testing ConditionalOperator
+ for (; i ? j : k; ) {} // expected-warning {{variables 'i' 'j' and 'k' used in loop condition not modified in loop body}}
+ for (; i ? j : k; ) { ++i; }
+ for (; i ? j : k; ) { ++j; }
+ for (; i ? j : k; ) { ++k; }
+ for (; i; ) { j = i ? i : i; } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; i; ) { j = (i = 1) ? i : i; }
+ for (; i; ) { j = i ? i : ++i; }
+
+ // Testing BinaryConditionalOperator
+ for (; i ?: j; ) {} // expected-warning {{variables 'i' and 'j' used in loop condition not modified in loop body}}
+ for (; i ?: j; ) { ++i; }
+ for (; i ?: j; ) { ++j; }
+ for (; i; ) { j = i ?: i; } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+
+ // Testing ParenExpr
+ for (; (i); ) { } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; (i); ) { ++i; }
+
+ // Testing non-evaluated variables
+ for (; i < sizeof(j); ) { } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; i < sizeof(j); ) { ++j; } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+ for (; i < sizeof(j); ) { ++i; }
+}
+
+// False positive and how to silence.
+void test3() {
+ int x;
+ int *ptr = &x;
+ for (;x<5;) { *ptr = 6; } // expected-warning {{variable 'x' used in loop condition not modified in loop body}}
+
+ for (;x<5;) {
+ *ptr = 6;
+ (void)x;
+ }
+}
+
+// Check ordering and printing of variables. Max variables is currently 4.
+void test4() {
+ int a, b, c, d, e, f;
+ for (; a;); // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+ for (; a + b;); // expected-warning {{variables 'a' and 'b' used in loop condition not modified in loop body}}
+ for (; a + b + c;); // expected-warning {{variables 'a' 'b' and 'c' used in loop condition not modified in loop body}}
+ for (; a + b + c + d;); // expected-warning {{variables 'a' 'b' 'c' and 'd' used in loop condition not modified in loop body}}
+ for (; a + b + c + d + e;); // expected-warning {{variables used in loop condition not modified in loop body}}
+ for (; a + b + c + d + e + f;); // expected-warning {{variables used in loop condition not modified in loop body}}
+ for (; a + c + d + b;); // expected-warning {{variables 'a' 'c' 'd' and 'b' used in loop condition not modified in loop body}}
+ for (; d + c + b + a;); // expected-warning {{variables 'd' 'c' 'b' and 'a' used in loop condition not modified in loop body}}
+}
+
+// Ensure that the warning doesn't fail when lots of variables are used
+// in the conditional.
+void test5() {
+ for (int a; a+a+a+a+a+a+a+a+a+a;); // \
+ // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+ for (int a; a+a+a+a+a+a+a+a+a+a+a;); // \
+ // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+ for (int a; a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a;); // \
+ // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+ for (int a; a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a;);//\
+ // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+}