[CFG] [analyzer] Don't treat argument constructors as temporary constructors.

Function argument constructors (that are used for passing objects into functions
by value) are completely unlike temporary object constructors, but we were
treating them as such because they are also wrapped into a CXXBindTemporaryExpr.

This patch adds a partial construction context layer for call argument values,
but doesn't proceed to transform it into an actual construction context yet.
This is tells the clients that we aren't supporting these constructors yet.

Differential Revision: https://reviews.llvm.org/D45650

llvm-svn: 330377

1 files changed, 7 insertions, 0 deletions

diff --git a/clang/lib/Analysis/CFG.cpp b/clang/lib/Analysis/CFG.cpp
index 34d40162275..66019329a3b 100644
--- a/clang/lib/Analysis/CFG.cpp
+++ b/clang/lib/Analysis/CFG.cpp
@@ -2367,6 +2367,13 @@ CFGBlock *CFGBuilder::VisitCallExpr(CallExpr *C, AddStmtChoice asc) {
     if (!boundType.isNull()) calleeType = boundType;
   }
 
+  // FIXME: Once actually implemented, this construction context layer should
+  // include the number of the argument as well.
+  for (auto Arg: C->arguments()) {
+    findConstructionContexts(
+        ConstructionContextLayer::create(cfg->getBumpVectorContext(), C), Arg);
+  }
+
   // If this is a call to a no-return function, this stops the block here.
   bool NoReturn = getFunctionExtInfo(*calleeType).getNoReturn();