From: Mike Stump <mrs@apple.com>
Date: Tue, 5 Jan 2010 02:56:35 +0000 (+0000)
Subject: Disallow capturing vlas inside blocks.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=0d6fd570e52f5d7fc637c9f41382992a97b94b4c;p=clang

Disallow capturing vlas inside blocks.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@92676 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 14271c8d90..1f8934e076 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1721,6 +1721,8 @@ def warn_printf_nonliteral : Warning<
 def err_unexpected_interface : Error<
   "unexpected interface name %0: expected expression">;
 def err_ref_non_value : Error<"%0 does not refer to a value">;
+def err_ref_vm_type : Error<
+  "cannot refer to declaration with a variably modified type inside block">;
 def err_property_not_found : Error<
   "property %0 not found on object of type %1">;
 def err_duplicate_property : Error<
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index d291cbb394..f0d39dde9f 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -1531,6 +1531,12 @@ Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS,
   // as they do not get snapshotted.
   //
   if (CurBlock && ShouldSnapshotBlockValueReference(CurBlock, VD)) {
+    if (VD->getType().getTypePtr()->isVariablyModifiedType()) {
+      Diag(Loc, diag::err_ref_vm_type);
+      Diag(D->getLocation(), diag::note_declared_at);
+      return ExprError();
+    }
+
     MarkDeclarationReferenced(Loc, VD);
     QualType ExprTy = VD->getType().getNonReferenceType();
     // The BlocksAttr indicates the variable is bound by-reference.
diff --git a/test/Sema/block-misc.c b/test/Sema/block-misc.c
index 9f1bc4025f..bc30552302 100644
--- a/test/Sema/block-misc.c
+++ b/test/Sema/block-misc.c
@@ -197,4 +197,14 @@ L0:
   return x;
 }
 
-
+// radr://7438948
+void test20() {
+  int n = 7;
+  int vla[n]; // expected-note {{declared at}}
+  int (*vm)[n] = 0; // expected-note {{declared at}}
+  vla[1] = 4341;
+  ^{
+    (void)vla[1];  // expected-error {{cannot refer to declaration with a variably modified type inside block}}
+    (void)(vm+1);  // expected-error {{cannot refer to declaration with a variably modified type inside block}}
+  }();
+}