[cfe-commits] r128681 - in /cfe/trunk: lib/Analysis/UninitializedValues.cpp test/Sema/uninit-variables.c

[Ted Kremenek]

Author: kremenek
Date: Thu Mar 31 17:32:41 2011
New Revision: 128681

URL: http://llvm.org/viewvc/llvm-project?rev=128681&view=rev
Log:
-Wuninitialized should not warn about variables captured by blocks as byref.

Note this can potentially be enhanced to detect if the __block variable
is actually written by the block, or only when the block "escapes" or
is actually used, but that requires more analysis than it is probably worth
for this simple check.

Modified:
    cfe/trunk/lib/Analysis/UninitializedValues.cpp
    cfe/trunk/test/Sema/uninit-variables.c

Modified: cfe/trunk/lib/Analysis/UninitializedValues.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/UninitializedValues.cpp?rev=128681&r1=128680&r2=128681&view=diff
==============================================================================
--- cfe/trunk/lib/Analysis/UninitializedValues.cpp (original)
+++ cfe/trunk/lib/Analysis/UninitializedValues.cpp Thu Mar 31 17:32:41 2011
@@ -440,13 +440,18 @@
 void TransferFunctions::VisitBlockExpr(BlockExpr *be) {
   if (!flagBlockUses || !handler)
     return;
-  AnalysisContext::referenced_decls_iterator i, e;
-  llvm::tie(i, e) = ac.getReferencedBlockVars(be->getBlockDecl());
-  for ( ; i != e; ++i) {
-    const VarDecl *vd = *i;
-    if (vd->getAttr<BlocksAttr>() || !vd->hasLocalStorage() || 
-        !isTrackedVar(vd))
+  const BlockDecl *bd = be->getBlockDecl();
+  for (BlockDecl::capture_const_iterator i = bd->capture_begin(),
+        e = bd->capture_end() ; i != e; ++i) {
+    const VarDecl *vd = i->getVariable();
+    if (!vd->hasLocalStorage())
       continue;
+    if (!isTrackedVar(vd))
+      continue;
+    if (i->isByRef()) {
+      vals[vd] = Initialized;
+      continue;
+    }
     Value v = vals[vd];
     if (isUninitialized(v))
       handler->handleUseOfUninitVariable(be, vd, isAlwaysUninit(v));

Modified: cfe/trunk/test/Sema/uninit-variables.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/uninit-variables.c?rev=128681&r1=128680&r2=128681&view=diff
==============================================================================
--- cfe/trunk/test/Sema/uninit-variables.c (original)
+++ cfe/trunk/test/Sema/uninit-variables.c Thu Mar 31 17:32:41 2011
@@ -328,3 +328,12 @@
   char c[1 ? : 2]; // no-warning
 }
 
+int test51(void)
+{
+    __block int a;
+    ^(void) {
+      a = 42;
+    }();
+    return a; // no-warning
+}
+