diff --git a/clang/include/clang/Basic/DiagnosticKinds.def b/clang/include/clang/Basic/DiagnosticKinds.def
index 2fd6ac5afed9..a85e0df32483 100644
--- a/clang/include/clang/Basic/DiagnosticKinds.def
+++ b/clang/include/clang/Basic/DiagnosticKinds.def
@@ -978,8 +978,6 @@ DIAG(err_redefinition_of_enumerator, ERROR,
      "redefinition of enumerator %0")
 DIAG(err_duplicate_member, ERROR,
      "duplicate member %0")
-DIAG(err_enum_value_not_integer_constant_expr, ERROR,
-     "enumerator value for %0 is not an integer constant")
 DIAG(ext_enum_value_not_int, EXTENSION,
      "ISO C restricts enumerator values to range of 'int' (%0 is too large)")
 DIAG(warn_enum_too_large, WARNING,
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 411307522be7..4fd13c3f96b7 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -2899,8 +2899,7 @@ Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl,
     
     // C99 6.7.2.2p2: Make sure we have an integer constant expression.
     SourceLocation ExpLoc;
-    if (!Val->isIntegerConstantExpr(EnumVal, Context, &ExpLoc)) {
-      Diag(ExpLoc, diag::err_enum_value_not_integer_constant_expr) << Id;
+    if (VerifyIntegerConstantExpression(Val, &EnumVal)) {
       delete Val;
       Val = 0;  // Just forget about it.
     } else {
diff --git a/clang/test/Sema/PR2963-enum-constant.c b/clang/test/Sema/PR2963-enum-constant.c
new file mode 100644
index 000000000000..28becc379375
--- /dev/null
+++ b/clang/test/Sema/PR2963-enum-constant.c
@@ -0,0 +1,17 @@
+// RUN: clang %s -verify -pedantic -fsyntax-only
+
+typedef short short_fixed;
+
+enum
+{
+        // 8.8 short_fixed
+        SHORT_FIXED_FRACTIONAL_BITS= 8,
+        SHORT_FIXED_ONE= 1<<SHORT_FIXED_FRACTIONAL_BITS
+};
+
+#define FLOAT_TO_SHORT_FIXED(f) ((short_fixed)((f)*SHORT_FIXED_ONE))
+
+enum
+{
+        SOME_VALUE= FLOAT_TO_SHORT_FIXED(0.1)
+};