Add initial version of "IteratorsChecker", a checker to find misues uses of C++ iterators.
This checker was created by Jim Goodnow II, and I migrated it to the
new Checker interface (recent changes by Argiris).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@127525 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Analysis/iterators.cpp b/test/Analysis/iterators.cpp
new file mode 100644
index 0000000..21d108b
--- /dev/null
+++ b/test/Analysis/iterators.cpp
@@ -0,0 +1,104 @@
+// RUN: %clang_cc1 -analyze -analyzer-checker=core,core.experimental.Iterators -verify %s
+
+#include <vector>
+
+void fum(std::vector<int>::iterator t);
+
+void foo1()
+{
+ // iterators that are defined but not initialized
+ std::vector<int>::iterator it2;
+ fum(it2); // expected-warning{{Use of iterator that is not defined}}
+ *it2; // expected-warning{{Use of iterator that is not defined}}
+
+ std::vector<int> v, vv;
+ std::vector<int>::iterator it = v.begin();
+ fum(it); // no-warning
+ *it; // no-warning
+ // a valid iterator plus an integer is still valid
+ std::vector<int>::iterator et = it + 3;
+ while(it != et) { // no-warning
+ if (*it == 0) // no-warning
+ *it = 1; // no-warning
+ }
+ // iterators from different instances Cannot be compared
+ et = vv.end();
+ while(it != et) // expected-warning{{Cannot compare iterators from different containers}}
+ ;
+
+ for( std::vector<int>::iterator it = v.begin(); it != v.end(); it++ ) { // no-warning
+ if (*it == 1) // no-warning
+ *it = 0; // no-warning
+ }
+
+ // copying a valid iterator results in a valid iterator
+ et = it; // no-warning
+ *et; // no-warning
+
+ // any combo of valid iterator plus a constant is still valid
+ et = it + 2; // no-warning
+ *et; // no-warning
+ et = 2 + it; // no-warning
+ *et; // no-warning
+ et = 2 + 4 + it; // no-warning
+ *et; // no-warning
+
+ // calling insert invalidates unless assigned to as result, but still
+ // invalidates other iterators on the same instance
+ it = v.insert( it, 1 ); // no-warning
+ *et; // expected-warning{{Attempt to use an iterator made invalid by call to 'insert'}}
+ ++it; // no-warning
+
+ // calling erase invalidates the iterator
+ v.erase(it); // no-warning
+ et = it + 2; // expected-warning{{Attempt to use an iterator made invalid by call to 'erase'}}
+ et = 2 + it + 2; // expected-warning{{Attempt to use an iterator made invalid by call to 'erase'}}
+ et = 2 + it; // expected-warning{{Attempt to use an iterator made invalid by call to 'erase'}}
+ ++it; // expected-warning{{Attempt to use an iterator made invalid by call to 'erase'}}
+ it++; // expected-warning{{Attempt to use an iterator made invalid by call to 'erase'}}
+ *it; // expected-warning{{Attempt to use an iterator made invalid by call to 'erase'}}
+ it = v.insert( it, 1 ); // expected-warning{{Attempt to use an iterator made invalid by call to 'erase'}}
+ // now valid after return from insert
+ *it; // no-warning
+}
+
+// work with using namespace
+void foo2()
+{
+ using namespace std;
+
+ vector<int> v;
+ vector<int>::iterator it = v.begin();
+ *it; // no-warning
+ v.insert( it, 1 ); // no-warning
+ *it; // expected-warning{{Attempt to use an iterator made invalid by call to 'insert'}}
+ it = v.insert( it, 1 ); // expected-warning{{Attempt to use an iterator made invalid by call to 'insert'}}
+ *it; // no-warning
+}
+
+// using reserve eliminates some warnings
+void foo3()
+{
+ std::vector<long> v;
+ std::vector<long>::iterator b = v.begin();
+ v.reserve( 100 );
+
+ // iterator assigned before the reserve is still invalidated
+ *b; // expected-warning{{Attempt to use an iterator made invalid by call to 'reserve'}}
+ b = v.begin();
+ v.insert( b, 1 ); // no-warning
+
+ // iterator after assignment is still valid (probably)
+ *b; // no-warning
+}
+
+// check on copying one iterator to another
+void foo4()
+{
+ std::vector<float> v, vv;
+ std::vector<float>::iterator it = v.begin();
+ *it; // no-warning
+ v = vv;
+ *it; // expected-warning{{Attempt to use an iterator made invalid by copying another container to its container}}
+}
+