From: Daniel Dunbar <daniel@zuster.org>
Date: Mon, 16 Feb 2009 23:37:57 +0000 (+0000)
Subject: Diagnose non-power-of-2 arguments to attribute aligned.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=396b2a22788b0134018760d6a476de1e20f81334;p=clang

Diagnose non-power-of-2 arguments to attribute aligned.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@64700 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.def b/include/clang/Basic/DiagnosticSemaKinds.def
index af4c7f5aa4..8514b92214 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.def
+++ b/include/clang/Basic/DiagnosticSemaKinds.def
@@ -356,6 +356,8 @@ DIAG(err_as_qualified_auto_decl, ERROR,
      "automatic variable qualified with an address space")
 DIAG(err_attribute_annotate_no_string, ERROR,
      "argument to annotate attribute was not a string literal")
+DIAG(err_attribute_aligned_not_power_of_two, ERROR,
+     "requested alignment is not a power of 2")
 DIAG(warn_redeclaration_without_attribute_prev_attribute_ignored, WARNING,
   "'%0' redeclared without %1 attribute: previous %1 ignored")
 DIAG(warn_attribute_ignored, WARNING,
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index a28d0a6d6d..1d83605316 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -1218,6 +1218,12 @@ static void HandleAlignedAttr(Decl *d, const AttributeList &Attr, Sema &S) {
       << "aligned" << alignmentExpr->getSourceRange();
     return;
   }
+  if (!llvm::isPowerOf2_64(Alignment.getZExtValue())) {
+    S.Diag(Attr.getLoc(), diag::err_attribute_aligned_not_power_of_two) 
+      << alignmentExpr->getSourceRange();
+    return;
+  }
+
   d->addAttr(new AlignedAttr(Alignment.getZExtValue() * 8));
 }
 
diff --git a/test/Sema/attr-aligned.c b/test/Sema/attr-aligned.c
new file mode 100644
index 0000000000..390e6d9df4
--- /dev/null
+++ b/test/Sema/attr-aligned.c
@@ -0,0 +1,3 @@
+// RUN: clang -fsyntax-only -verify %s
+
+int x __attribute__((aligned(3))); // expected-error {{requested alignment is not a power of 2}}