From: John McCall <rjmccall@apple.com>
Date: Thu, 24 Dec 2009 11:09:08 +0000 (+0000)
Subject: Fix the clang-on-clang build:  APFloat reports underflow whenever we get a
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9f2df88757c8db3d97fa198f0ad4b6f139baa66a;p=clang

Fix the clang-on-clang build:  APFloat reports underflow whenever we get a
denormal, but we only want to diagnose if we underflowed to zero.  This
allows people to write constants in the denormal range.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@92129 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 0951677db2..a6b409b99f 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -1589,7 +1589,11 @@ Action::OwningExprResult Sema::ActOnNumericConstant(const Token &Tok) {
     APFloat Val(Format);
 
     APFloat::opStatus result = Literal.GetFloatValue(Val);
-    if (result & (APFloat::opOverflow | APFloat::opUnderflow)) {
+
+    // Overflow is always an error, but underflow is only an error if
+    // we underflowed to zero (APFloat reports denormals as underflow).
+    if ((result & APFloat::opOverflow) ||
+        ((result & APFloat::opUnderflow) && Val.isZero())) {
       unsigned diagnostic;
       llvm::SmallVector<char, 20> buffer;
       if (result & APFloat::opOverflow) {