[cfe-commits] r113826 - in /cfe/trunk: lib/Analysis/CFG.cpp test/Analysis/misc-ps-region-store.m

[Ted Kremenek]

Author: kremenek
Date: Mon Sep 13 20:13:32 2010
New Revision: 113826

URL: http://llvm.org/viewvc/llvm-project?rev=113826&view=rev
Log:
Fix CFGBuilder crash reported in PR 8141.

Modified:
    cfe/trunk/lib/Analysis/CFG.cpp
    cfe/trunk/test/Analysis/misc-ps-region-store.m

Modified: cfe/trunk/lib/Analysis/CFG.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/CFG.cpp?rev=113826&r1=113825&r2=113826&view=diff
==============================================================================
--- cfe/trunk/lib/Analysis/CFG.cpp (original)
+++ cfe/trunk/lib/Analysis/CFG.cpp Mon Sep 13 20:13:32 2010
@@ -525,8 +525,12 @@
       AppendStmt(Block, B, asc);
     }
 
-    Visit(B->getRHS());
-    return Visit(B->getLHS(), AddStmtChoice::AsLValueNotAlwaysAdd);
+    // If visiting RHS causes us to finish 'Block' and the LHS doesn't
+    // create a new block, then we should return RBlock.  Otherwise
+    // we'll incorrectly return NULL.
+    CFGBlock *RBlock = Visit(B->getRHS());
+    CFGBlock *LBlock = Visit(B->getLHS(), AddStmtChoice::AsLValueNotAlwaysAdd);
+    return LBlock ? LBlock : RBlock;
   }
 
   return VisitStmt(B, asc);

Modified: cfe/trunk/test/Analysis/misc-ps-region-store.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/misc-ps-region-store.m?rev=113826&r1=113825&r2=113826&view=diff
==============================================================================
--- cfe/trunk/test/Analysis/misc-ps-region-store.m (original)
+++ cfe/trunk/test/Analysis/misc-ps-region-store.m Mon Sep 13 20:13:32 2010
@@ -1142,3 +1142,17 @@
   }
 }
 
+// PR 8141.  Previously the statement expression in the for loop caused
+// the CFG builder to crash.
+struct list_pr8141
+{
+  struct list_pr8141 *tail;
+};
+
+struct list_pr8141 *
+pr8141 (void) {
+  struct list_pr8141 *items;
+  for (;; items = ({ do { } while (0); items->tail; })) // expected-warning{{Dereference of undefined pointer value}}
+    {
+    }
+}