[cfe-commits] r114314 - in /cfe/trunk: lib/AST/Expr.cpp lib/Sema/SemaStmt.cpp test/Sema/warn-unused-value.c

[Argyrios Kyrtzidis]

Author: akirtzidis
Date: Sun Sep 19 16:21:10 2010
New Revision: 114314

URL: http://llvm.org/viewvc/llvm-project?rev=114314&view=rev
Log:
Warn when an expression result in a LabelStmt is unused.

Modified:
    cfe/trunk/lib/AST/Expr.cpp
    cfe/trunk/lib/Sema/SemaStmt.cpp
    cfe/trunk/test/Sema/warn-unused-value.c

Modified: cfe/trunk/lib/AST/Expr.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/Expr.cpp?rev=114314&r1=114313&r2=114314&view=diff
==============================================================================
--- cfe/trunk/lib/AST/Expr.cpp (original)
+++ cfe/trunk/lib/AST/Expr.cpp Sun Sep 19 16:21:10 2010
@@ -1225,9 +1225,13 @@
     // however, if the result of the stmt expr is dead, we don't want to emit a
     // warning.
     const CompoundStmt *CS = cast<StmtExpr>(this)->getSubStmt();
-    if (!CS->body_empty())
+    if (!CS->body_empty()) {
       if (const Expr *E = dyn_cast<Expr>(CS->body_back()))
         return E->isUnusedResultAWarning(Loc, R1, R2, Ctx);
+      if (const LabelStmt *Label = dyn_cast<LabelStmt>(CS->body_back()))
+        if (const Expr *E = dyn_cast<Expr>(Label->getSubStmt()))
+          return E->isUnusedResultAWarning(Loc, R1, R2, Ctx);
+    }
 
     if (getType()->isVoidType())
       return false;

Modified: cfe/trunk/lib/Sema/SemaStmt.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaStmt.cpp?rev=114314&r1=114313&r2=114314&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaStmt.cpp (original)
+++ cfe/trunk/lib/Sema/SemaStmt.cpp Sun Sep 19 16:21:10 2010
@@ -67,6 +67,9 @@
 }
 
 void Sema::DiagnoseUnusedExprResult(const Stmt *S) {
+  if (const LabelStmt *Label = dyn_cast_or_null<LabelStmt>(S))
+    return DiagnoseUnusedExprResult(Label->getSubStmt());
+
   const Expr *E = dyn_cast_or_null<Expr>(S);
   if (!E)
     return;

Modified: cfe/trunk/test/Sema/warn-unused-value.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/warn-unused-value.c?rev=114314&r1=114313&r2=114314&view=diff
==============================================================================
--- cfe/trunk/test/Sema/warn-unused-value.c (original)
+++ cfe/trunk/test/Sema/warn-unused-value.c Sun Sep 19 16:21:10 2010
@@ -52,6 +52,9 @@
   volatile int* pj = &j;
   *pi;              // expected-warning {{expression result unused}}
   *pj;
+
+  foo_label:
+  i;                // expected-warning {{expression result unused}}
 }
 
 // Don't warn about unused '||', '&&' expressions that contain assignments.