[PATCH] Attempt to fix up condition variables with temp dtors.

[Manuel Klimek]

Hi krememek, jordan_rose,

I discovered this problem when playing around with slightly
different block split-ups when inserting temp dtors; a test
would fail with "garbage value accessed" warning. After following
some red herrings while debugging, I realized that the initializer
(MyClass c = ...) was after the temp destructor call (see the test
I had to fix). I just replaced the special-case logic in VisitIfStmt
with a call to addStmt, which invokes VisitDeclStmt, which already
handles all the temporary destructor logic correctly.
If you can come up with tests that this breaks, please let me know ;)

http://reviews.llvm.org/D3603

Files:
  lib/Analysis/CFG.cpp
  test/Analysis/temp-obj-dtors-cfg-output.cpp

Index: lib/Analysis/CFG.cpp
===================================================================
--- lib/Analysis/CFG.cpp
+++ lib/Analysis/CFG.cpp
@@ -2107,14 +2107,12 @@
   // blocks will be pointed to be "Block".
   CFGBlock *LastBlock = addStmt(I->getCond());
 
-  // Finally, if the IfStmt contains a condition variable, add both the IfStmt
-  // and the condition variable initialization to the CFG.
+  // Finally, if the IfStmt contains a condition variable, add it and its
+  // initializer to the CFG.
   if (VarDecl *VD = I->getConditionVariable()) {
-    if (Expr *Init = VD->getInit()) {
-      autoCreateBlock();
-      appendStmt(Block, I->getConditionVariableDeclStmt());
-      LastBlock = addStmt(Init);
-    }
+    autoCreateBlock();
+    LastBlock =
+        addStmt(const_cast<DeclStmt *>(I->getConditionVariableDeclStmt()));
   }
 
   return LastBlock;
Index: test/Analysis/temp-obj-dtors-cfg-output.cpp
===================================================================
--- test/Analysis/temp-obj-dtors-cfg-output.cpp
+++ test/Analysis/temp-obj-dtors-cfg-output.cpp
@@ -611,28 +611,28 @@
 // CHECK:   [B5 (ENTRY)]
 // CHECK:     Succs (1): B4
 // CHECK:   [B1]
-// CHECK:     1: [B4.7].~C() (Implicit destructor)
+// CHECK:     1: [B4.6].~C() (Implicit destructor)
 // CHECK:     Succs (1): B0
 // CHECK:   [B2]
 // CHECK:     1: 0
 // CHECK:     2: return [B2.1];
-// CHECK:     3: [B4.7].~C() (Implicit destructor)
+// CHECK:     3: [B4.6].~C() (Implicit destructor)
 // CHECK:     Preds (1): B4
 // CHECK:     Succs (1): B0
 // CHECK:   [B3]
 // CHECK:     1: 1
 // CHECK:     2: return [B3.1];
-// CHECK:     3: [B4.7].~C() (Implicit destructor)
+// CHECK:     3: [B4.6].~C() (Implicit destructor)
 // CHECK:     Preds (1): B4
 // CHECK:     Succs (1): B0
 // CHECK:   [B4]
 // CHECK:     1: C() (CXXConstructExpr, struct C)
 // CHECK:     2: [B4.1] (BindTemporary)
 // CHECK:     3: [B4.2] (ImplicitCastExpr, NoOp, const struct C)
 // CHECK:     4: [B4.3]
 // CHECK:     5: [B4.4] (CXXConstructExpr, struct C)
-// CHECK:     6: ~C() (Temporary object destructor)
-// CHECK:     7: C c = C();
+// CHECK:     6: C c = C();
+// CHECK:     7: ~C() (Temporary object destructor)
 // CHECK:     8: c
 // CHECK:     9: [B4.8].operator bool
 // CHECK:    10: [B4.8]
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