[cfe-commits] r103360 - in /cfe/trunk: lib/AST/Expr.cpp lib/Sema/SemaOverload.cpp test/Sema/unused-expr.c

[Douglas Gregor]

Author: dgregor
Date: Sat May  8 17:41:50 2010
New Revision: 103360

URL: http://llvm.org/viewvc/llvm-project?rev=103360&view=rev
Log:
Don't complain about an __builtin_va_arg expression's result being
unused, since the operation has side effects.

Modified:
    cfe/trunk/lib/AST/Expr.cpp
    cfe/trunk/lib/Sema/SemaOverload.cpp
    cfe/trunk/test/Sema/unused-expr.c

Modified: cfe/trunk/lib/AST/Expr.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/Expr.cpp?rev=103360&r1=103359&r2=103360&view=diff
==============================================================================
--- cfe/trunk/lib/AST/Expr.cpp (original)
+++ cfe/trunk/lib/AST/Expr.cpp Sat May  8 17:41:50 2010
@@ -976,6 +976,7 @@
     return true;
   }
   case CompoundAssignOperatorClass:
+  case VAArgExprClass:
     return false;
 
   case ConditionalOperatorClass: {

Modified: cfe/trunk/lib/Sema/SemaOverload.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaOverload.cpp?rev=103360&r1=103359&r2=103360&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaOverload.cpp (original)
+++ cfe/trunk/lib/Sema/SemaOverload.cpp Sat May  8 17:41:50 2010
@@ -2910,6 +2910,7 @@
 /// TryContextuallyConvertToBool - Attempt to contextually convert the
 /// expression From to bool (C++0x [conv]p3).
 ImplicitConversionSequence Sema::TryContextuallyConvertToBool(Expr *From) {
+  // FIXME: This is pretty broken.
   return TryImplicitConversion(From, Context.BoolTy,
                                // FIXME: Are these flags correct?
                                /*SuppressUserConversions=*/false,

Modified: cfe/trunk/test/Sema/unused-expr.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/unused-expr.c?rev=103360&r1=103359&r2=103360&view=diff
==============================================================================
--- cfe/trunk/test/Sema/unused-expr.c (original)
+++ cfe/trunk/test/Sema/unused-expr.c Sat May  8 17:41:50 2010
@@ -110,3 +110,11 @@
 void t10() {
   (void*) some_function(); //expected-warning {{expression result unused; should this cast be to 'void'?}}
 }
+
+void f(int i, ...) {
+    __builtin_va_list ap;
+    
+    __builtin_va_start(ap, i);
+    __builtin_va_arg(ap, int);
+    __builtin_va_end(ap);
+}