[clang] be86fdb - [analyzer] Fix off-by-one in operator call parameter binding.

[Artem Dergachev via cfe-commits]

Author: Artem Dergachev
Date: 2019-10-23T08:17:02-07:00
New Revision: be86fdb86e1efd6921c81f25ac0c0a78903c0a2d

URL: https://github.com/llvm/llvm-project/commit/be86fdb86e1efd6921c81f25ac0c0a78903c0a2d
DIFF: https://github.com/llvm/llvm-project/commit/be86fdb86e1efd6921c81f25ac0c0a78903c0a2d.diff

LOG: [analyzer] Fix off-by-one in operator call parameter binding.

Member operator declarations and member operator expressions
have different numbering of parameters and arguments respectively:
one of them includes "this", the other does not.

Account for this inconsistency when figuring out whether
the parameter needs to be manually rebound from the Environment
to the Store when entering a stack frame of an operator call,
as opposed to being constructed with a constructor and as such
already having the necessary Store bindings.

Differential Revision: https://reviews.llvm.org/D69155

Added: 
    

Modified: 
    clang/lib/StaticAnalyzer/Core/CallEvent.cpp
    clang/test/Analysis/temporaries.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/StaticAnalyzer/Core/CallEvent.cpp b/clang/lib/StaticAnalyzer/Core/CallEvent.cpp
index 5f04a59ba055..d95f809bec1a 100644
--- a/clang/lib/StaticAnalyzer/Core/CallEvent.cpp
+++ b/clang/lib/StaticAnalyzer/Core/CallEvent.cpp
@@ -519,7 +519,7 @@ static void addParameterValuesToBindings(const StackFrameContext *CalleeCtx,
 
     // TODO: Support allocator calls.
     if (Call.getKind() != CE_CXXAllocator)
-      if (Call.isArgumentConstructedDirectly(Idx))
+      if (Call.isArgumentConstructedDirectly(Call.getASTArgumentIndex(Idx)))
         continue;
 
     // TODO: Allocators should receive the correct size and possibly alignment,

diff  --git a/clang/test/Analysis/temporaries.cpp b/clang/test/Analysis/temporaries.cpp
index 012cef52f14e..325b689c0deb 100644
--- a/clang/test/Analysis/temporaries.cpp
+++ b/clang/test/Analysis/temporaries.cpp
@@ -1231,3 +1231,19 @@ S bar3(int coin) {
   return coin ? S() : foo(); // no-warning
 }
 } // namespace return_from_top_frame
+
+#if __cplusplus >= 201103L
+namespace arguments_of_operators {
+struct S {
+  S() {}
+  S(const S &) {}
+};
+
+void test() {
+  int x = 0;
+  auto foo = [](S s, int &y) { y = 1; };
+  foo(S(), x);
+  clang_analyzer_eval(x == 1); // expected-warning{{TRUE}}
+}
+} // namespace arguments_of_operators
+#endif // __cplusplus >= 201103L