r175281 - When a statement is dropped from the AST because it was invalid, make sure

[Argyrios Kyrtzidis]

Author: akirtzidis
Date: Fri Feb 15 12:34:13 2013
New Revision: 175281

URL: http://llvm.org/viewvc/llvm-project?rev=175281&view=rev
Log:
When a statement is dropped from the AST because it was invalid, make sure
we don't do the scope checks otherwise we are going to hit assertion checks
since a label may not have been actually added.

Modified:
    cfe/trunk/include/clang/Sema/ScopeInfo.h
    cfe/trunk/lib/Parse/ParseStmt.cpp
    cfe/trunk/lib/Sema/SemaStmt.cpp
    cfe/trunk/test/SemaCXX/scope-check.cpp

Modified: cfe/trunk/include/clang/Sema/ScopeInfo.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Sema/ScopeInfo.h?rev=175281&r1=175280&r2=175281&view=diff
==============================================================================
--- cfe/trunk/include/clang/Sema/ScopeInfo.h (original)
+++ cfe/trunk/include/clang/Sema/ScopeInfo.h Fri Feb 15 12:34:13 2013
@@ -91,6 +91,9 @@ public:
   /// \brief Whether this function contains any indirect gotos.
   bool HasIndirectGoto;
 
+  /// \brief Whether a statement was dropped because it was invalid.
+  bool HasDroppedStmt;
+
   /// A flag that is set when parsing a method that must call super's
   /// implementation, such as \c -dealloc, \c -finalize, or any method marked
   /// with \c __attribute__((objc_requires_super)).
@@ -287,9 +290,14 @@ public:
     HasIndirectGoto = true;
   }
 
+  void setHasDroppedStmt() {
+    HasDroppedStmt = true;
+  }
+
   bool NeedsScopeChecking() const {
-    return HasIndirectGoto ||
-          (HasBranchProtectedScope && HasBranchIntoScope);
+    return !HasDroppedStmt &&
+        (HasIndirectGoto ||
+          (HasBranchProtectedScope && HasBranchIntoScope));
   }
   
   FunctionScopeInfo(DiagnosticsEngine &Diag)
@@ -297,6 +305,7 @@ public:
       HasBranchProtectedScope(false),
       HasBranchIntoScope(false),
       HasIndirectGoto(false),
+      HasDroppedStmt(false),
       ObjCShouldCallSuper(false),
       ErrorTrap(Diag) { }
 

Modified: cfe/trunk/lib/Parse/ParseStmt.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Parse/ParseStmt.cpp?rev=175281&r1=175280&r2=175281&view=diff
==============================================================================
--- cfe/trunk/lib/Parse/ParseStmt.cpp (original)
+++ cfe/trunk/lib/Parse/ParseStmt.cpp Fri Feb 15 12:34:13 2013
@@ -1042,11 +1042,6 @@ StmtResult Parser::ParseIfStatement(Sour
 
   IfScope.Exit();
 
-  // If the condition was invalid, discard the if statement.  We could recover
-  // better by replacing it with a valid expr, but don't do that yet.
-  if (CondExp.isInvalid() && !CondVar)
-    return StmtError();
-
   // If the then or else stmt is invalid and the other is valid (and present),
   // make turn the invalid one into a null stmt to avoid dropping the other
   // part.  If both are invalid, return error.

Modified: cfe/trunk/lib/Sema/SemaStmt.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaStmt.cpp?rev=175281&r1=175280&r2=175281&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaStmt.cpp (original)
+++ cfe/trunk/lib/Sema/SemaStmt.cpp Fri Feb 15 12:34:13 2013
@@ -406,6 +406,13 @@ StmtResult
 Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, Decl *CondVar,
                   Stmt *thenStmt, SourceLocation ElseLoc,
                   Stmt *elseStmt) {
+  // If the condition was invalid, discard the if statement.  We could recover
+  // better by replacing it with a valid expr, but don't do that yet.
+  if (!CondVal.get() && !CondVar) {
+    getCurFunction()->setHasDroppedStmt();
+    return StmtError();
+  }
+
   ExprResult CondResult(CondVal.release());
 
   VarDecl *ConditionVar = 0;

Modified: cfe/trunk/test/SemaCXX/scope-check.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/scope-check.cpp?rev=175281&r1=175280&r2=175281&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/scope-check.cpp (original)
+++ cfe/trunk/test/SemaCXX/scope-check.cpp Fri Feb 15 12:34:13 2013
@@ -274,3 +274,15 @@ namespace test15 {
     goto x; // expected-error {{goto into protected scope}}
   }
 }
+
+namespace test16 {
+Invalid inv; // expected-error {{unknown type name}}
+// Make sure this doesn't assert.
+void fn()
+{
+    int c = 0;
+    if (inv)
+Here: ;
+    goto Here;
+}
+}