[cfe-commits] r63562 - in /cfe/trunk: lib/Sema/SemaDecl.cpp test/Sema/static-init.c

[Nuno Lopes]

Author: nlopes
Date: Mon Feb  2 16:57:15 2009
New Revision: 63562

URL: http://llvm.org/viewvc/llvm-project?rev=63562&view=rev
Log:
emit diagnostic when casting a ptr to a small int when doing static initialization (addresses Eli's comments I believe)

Modified:
    cfe/trunk/lib/Sema/SemaDecl.cpp
    cfe/trunk/test/Sema/static-init.c

Modified: cfe/trunk/lib/Sema/SemaDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=63562&r1=63561&r2=63562&view=diff

==============================================================================
--- cfe/trunk/lib/Sema/SemaDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaDecl.cpp Mon Feb  2 16:57:15 2009
@@ -2055,14 +2055,23 @@
   }
   case Expr::ImplicitCastExprClass:
   case Expr::CStyleCastExprClass: {
-    const Expr *SubExpr = cast<CastExpr>(Init)->getSubExpr();
+    const CastExpr *CE = cast<CastExpr>(Init);
+    const Expr *SubExpr = CE->getSubExpr();
+
     if (SubExpr->getType()->isArithmeticType())
       return CheckArithmeticConstantExpression(SubExpr);
 
     if (SubExpr->getType()->isPointerType()) {
       const Expr* Base = FindExpressionBaseAddress(SubExpr);
-      // If the pointer has a null base, this is an offsetof-like construct
-      return Base ? false : CheckAddressConstantExpression(SubExpr);
+      if (Base) {
+        // the cast is only valid if done to a wide enough type
+        if (Context.getTypeSize(CE->getType()) >=
+            Context.getTypeSize(SubExpr->getType()))
+          return false;
+      } else {
+        // If the pointer has a null base, this is an offsetof-like construct
+        return CheckAddressConstantExpression(SubExpr);
+      }
     }
 
     InitializerElementNotConstant(Init);

Modified: cfe/trunk/test/Sema/static-init.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/static-init.c?rev=63562&r1=63561&r2=63562&view=diff

==============================================================================
--- cfe/trunk/test/Sema/static-init.c (original)
+++ cfe/trunk/test/Sema/static-init.c Mon Feb  2 16:57:15 2009
@@ -16,4 +16,5 @@
 };
 
 union bar u[1];
-struct foo x = {(int) u}; // no-error
+struct foo x = {(long) u}; // no-error
+struct foo y = {(char) u}; // expected-error {{initializer element is not a compile-time constant}}